JP6562750B2 - Electronic component, connection body, manufacturing method of connection body, connection method of electronic component, cushioning material - Google Patents

Description

  The present invention relates to an electronic component connected to a circuit board via an adhesive, a connection body in which the electronic component is connected to the circuit board, a manufacturing method of the connection body, a connection method of the electronic component, and a cushioning material. The present invention relates to an electronic component in which a plurality of bump electrodes are arranged on a mounting surface on a circuit board, a connection body to which the electronic component is connected, a method for manufacturing the connection body, a connection method for the electronic component, and a buffer material.

  2. Description of the Related Art Conventionally, a connection body is provided in which electronic components such as an IC chip and an LSI chip are connected to circuit boards of various electronic devices. In recent years, various electronic devices use IC chips or LSI chips in which bumps, which are protruding electrodes, are arranged on the mounting surface as electronic components from the viewpoints of fine pitch, light weight, and thinning. So-called COB (chip on board) or COG (chip on glass) for directly mounting electronic components on the circuit board is employed.

  In COB connection and COG connection, an IC chip is thermocompression-bonded on a terminal portion of a circuit board via an anisotropic conductive film. An anisotropic conductive film is a film formed by mixing conductive particles in a thermosetting binder resin, and heat conduction is performed between two conductors so that electrical conduction between the conductors is achieved with the conductive particles. The mechanical connection between the conductors is maintained by the binder resin. As an adhesive constituting the anisotropic conductive film, a highly reliable thermosetting adhesive is usually used. On the other hand, connection using a photo-curable resin or a connection method using both thermosetting and photo-curing is also used. However, in the case of applying pressure with a crimping tool, it is assumed that the same problems as thermosetting adhesives are included. Is done.

  For example, as shown in FIGS. 12A and 12B, the bumped IC chip 50 has an input bump area 52 in which input bumps 51 are arranged in a line along one side edge 50a on the mounting surface of the circuit board. An output bump region 54 in which output bumps 53 are arranged in two rows in a zigzag manner is provided along the other side edge 50b that is formed and faces one side edge 50a. The bump arrangement varies depending on the type of IC chip. In general, a conventional IC chip with bumps has a larger number of output bumps 53 than the number of input bumps 51, and an output bump area 54 than the area of the input bump area 52. And the shape of the input bump 51 is formed larger than the shape of the output bump 53.

  In COG mounting, after the IC chip 50 is mounted on the electrode terminal 57 of the circuit board 56 via the anisotropic conductive film 55, the thermocompression bonding tool 58 is used from above the IC chip 50 via the buffer material 60. Heat and press. By the heat pressing by the thermocompression bonding tool 58, the binder resin of the anisotropic conductive film 55 is melted and flows from between the input / output bumps 51, 53 and the electrode terminals 57 of the circuit board 56, and each input / output. Conductive particles are sandwiched between the bumps 51 and 53 and the electrode terminal 57 of the circuit board 56, and in this state, the binder resin is thermally cured. As a result, the IC chip 50 is electrically and mechanically connected to the circuit board 56.

JP 2004-214373 A

  Here, in the electronic component such as the IC chip 50 with bumps, the input bumps 51 are arranged along one side edge 50a and the output bumps 53 are arranged along the other side edge 50b on the mounting surface. An inter-bump area where no bump is formed is provided in the center. Therefore, in the conventional COB connection or COG connection, when the IC chip 50 is pressed by the thermocompression bonding tool 58, as shown in FIG. 13, the input / output bumps 51 provided on the inner sides of the side edges 50a, 50b, A warp occurs so that the central inter-bump region is recessed with 53 as a fulcrum.

  Further, the IC chip 50 has different bump arrangements and sizes of the input bumps 51 and the output bumps 53 formed on the mounting surface, and has an area difference between the input bump region 52 and the output bump region 54. Further, in the electronic component, the input bump area 52 and the output bump area 54 are asymmetrically arranged on the mounting surface.

  Therefore, in the IC chip 50, the pressing force applied to the input bump 51 and the output bump 53 becomes non-uniform. For example, in the output bump area 54, the output bump 53 arranged on the other side edge 50b side and the inner side of the mounting surface A difference in pressure may occur between the output bumps 53 arranged in the same manner.

  Further, when the pressure by the thermocompression bonding tool 58 is biased to the inner edges of the input bump area 52 and the output bump area 54, the output bump area 54 has an output bump 53 arranged on the other side edge 50 b side. There is a risk that the pressure of the electric field becomes weak and the conductive particles are insufficiently pushed to cause poor conduction.

  In order to solve such problems, so-called dummy bumps that are not used for signal input / output are formed, and stress applied from the thermocompression bonding tool to the entire surface of the IC chip is dispersed and made uniform. However, this technique also increases the technical difficulty by increasing the stress fulcrum. Further, in order to form dummy bumps, the number of man-hours for manufacturing electronic components increases, and material costs are also required. Therefore, a configuration that does not use dummy bumps is desired.

  Therefore, the present invention eliminates the pressure difference caused by the thermocompression bonding tool and improves the connection reliability in the electronic component in which the input bump area and the output bump area are arranged along opposite side edges of the mounting surface. It is an object of the present invention to provide an electronic component, a connection body, a connection body manufacturing method, an electronic component connection method, and a cushioning material.

In order to solve the above-described problems, an electronic component according to the present invention has an output bump region in which output bumps are arranged along one side of a pair of side edges facing each other on a mounting surface connected to a circuit board. An input bump area is provided in which input bumps are arranged along the other side of the pair of side edges, and the output bump area and the pressing bump are pressed against a pressing tool opposite to the mounting surface. A concave portion that overlaps with an inter-bump region between the input bump region is provided , and an end portion on one side of the output bump region or the input bump region of the concave portion is arranged on the innermost side of the one bump region. The length of the one bump region in the width direction from the inner edge of the row toward the side edge where the one bump region in the width direction orthogonal to the bump arrangement direction of the one bump region is provided. 12.5 And a region of less than 50% of the length in the width direction of the one bump region toward the side edge side where the other bump region in the width direction of the one bump region is provided. It is what is located.

Further, the connection body according to the present invention is a connection body in which the electronic component is arranged on the circuit board via an adhesive and pressed by a crimping tool so that the electronic component is connected to the circuit board. The electronic component is provided with an output bump area in which output bumps are arranged along one side of a pair of opposite side edges on a mounting surface connected to the circuit board, and the other of the pair of side edges. An input bump region in which input bumps are arranged along the side is provided, and an inter-bump region between the output bump region and the input bump region is provided on the pressing surface pressed by the crimping tool opposite to the mounting surface. And an end of one side of the output bump area or the input bump area of the recess is formed from the inner edge of the bump row arranged on the innermost side of the one bump area, and the one bump Above the area A region of less than 12.5% of the length in the width direction of the one bump region toward the side edge side where the one bump region in the width direction orthogonal to the arrangement direction of the bumps is provided, and the one bump The region is located between the region of less than 50% of the length in the width direction of the one bump region toward the side edge side where the other bump region in the width direction is provided.

Moreover, the manufacturing method of the connection body which concerns on this invention arrange | positions an electronic component on a circuit board via an adhesive agent, and manufactures the connection body which connects the said electronic component on the said circuit board by pressurizing with a crimping tool. In the method, the electronic component is provided with an output bump area in which output bumps are arranged along one side of a pair of side edges facing each other on a mounting surface connected to the circuit board, and the pair of side edges An input bump area in which input bumps are arranged along the other side of the mounting bump is provided, and a bump between the output bump area and the input bump area is formed on the pressing surface pressed by the crimping tool opposite to the mounting surface. A concave portion is provided so as to overlap with an inter-region, and an end portion on one side of the output bump region or the input bump region of the concave portion is from the inner edge of the bump row arranged on the innermost side of the one bump region, The van An area of less than 12.5% of the length in the width direction of the one bump area toward the side edge side where the one bump area in the width direction orthogonal to the arrangement direction of the bumps in the area is provided; One bump region is located between the region of less than 50% of the length in the width direction of the one bump region toward the side edge side where the other bump region in the width direction is provided. is there.

The electronic component connection method according to the present invention is an electronic component connection method in which an electronic component is arranged on a circuit board via an adhesive and the electronic component is connected to the circuit board by applying pressure with a crimping tool. In the method, the electronic component is provided with an output bump area in which output bumps are arranged along one side of a pair of side edges facing each other on a mounting surface connected to the circuit board, and the pair of side edges An input bump area in which input bumps are arranged along the other side of the mounting bump is provided, and a bump between the output bump area and the input bump area is formed on the pressing surface pressed by the crimping tool opposite to the mounting surface. A concave portion is provided so as to overlap with an inter-region, and an end portion on one side of the output bump region or the input bump region of the concave portion is from the inner edge of the bump row arranged on the innermost side of the one bump region, of A region of less than 12.5% of the length in the width direction of the one bump region toward the side edge side where the one bump region in the width direction perpendicular to the arrangement direction of the bumps in the bump region is provided; Located between the one bump region and the region of less than 50% of the length in the width direction of the one bump region toward the side edge where the other bump region in the width direction is provided It is.

  Further, the cushioning material according to the present invention has an output bump area in which output bumps are arranged on a mounting surface connected to a circuit board, an input bump area in which input bumps are arranged to face the output bump area, A sheet-like cushioning material disposed between the pressing surface opposite to the mounting surface and the crimping tool of the electronic component having the bump area provided between the output bump area and the input bump area. In FIG. 2, a recess is formed at a position corresponding to the inter-bump region.

  Further, in the method for manufacturing a connection body according to the present invention, an electronic component is arranged on a circuit board via an adhesive, and the electronic component is connected to the circuit board by applying pressure with a crimping tool via a cushioning material. In the connection body manufacturing method, the electronic component includes an output bump area in which output bumps are arranged on a mounting surface connected to the circuit board, and an input in which input bumps are arranged to face the output bump areas. It has a bump area, an inter-bump area provided between the output bump area and the input bump area, and the cushioning material has a recess formed at a position corresponding to the inter-bump area. .

  Further, the electronic component connecting method according to the present invention is such that the electronic component is arranged on the circuit board via an adhesive, and the electronic component is connected to the circuit board by pressing with a crimping tool via a cushioning material. In the electronic component connecting method, the electronic component includes an output bump area in which output bumps are arranged on a mounting surface connected to the circuit board, and an input in which input bumps are arranged to face the output bump area. It has a bump area, an inter-bump area provided between the output bump area and the input bump area, and the cushioning material has a recess formed at a position corresponding to the inter-bump area. .

  According to the present invention, by providing the pressing surface pressed by the crimping tool with a recess overlapping the inter-bump region between the output bump region and the input bump region, the pressure of the crimping tool can be adjusted between the output bump region and the input bump. Concentrating on the region and suppressing warping, the output bump and the input bump are sufficiently pressed by the crimping tool. Therefore, the electronic component obtains good electrical conductivity between the input / output bumps and the input / output terminals provided on the circuit board.

  Further, according to the present invention, since the concave portion is formed at a position corresponding to the area between the bumps of the cushioning material disposed between the crimping tool and the electronic component, the pressure of the crimping tool is input to the output bump area. Concentrating on the bump area and suppressing warpage, the output bump and the input bump are sufficiently pressed by the crimping tool. Therefore, the electronic component obtains good electrical conductivity between the input / output bumps and the input / output terminals provided on the circuit board.

FIG. 1A is a cross-sectional view illustrating a connection process of an electronic component to which the present invention is applied, and FIG. 1B is a cross-sectional view illustrating a connection body. FIG. 2 is a plan view showing a mounting surface of the IC chip. FIG. 3 is a view showing an example of forming the pressing surface of the IC chip, (A) is a cross-sectional view showing a process of attaching the auxiliary member, and (B) is a recess formed by attaching the auxiliary member. It is sectional drawing which shows the IC chip in which was formed. FIG. 4A is a cross-sectional view showing an IC chip in which the end of the recess on the output bump region side is formed on the output bump region, and FIG. 4B is the end of the recess on the output bump region side. It is sectional drawing which shows the IC chip currently formed on the area | region between bumps. FIG. 5 is a plan view showing an IC chip in which dummy bumps are provided in the area between the bumps. FIG. 6 is a cross-sectional view showing an anisotropic conductive film. FIG. 7A is a cross-sectional view illustrating a connection process of an electronic component using a buffer material in which a recess is formed, and FIG. 7B is a cross-sectional view illustrating a connection body. FIG. 8 is a perspective view showing the cushioning material. FIG. 9 is a side view showing a step of forming the uneven portion of the cushioning material. FIG. 10 is a plan view showing the configuration of the cushioning material according to the transport direction, (A) shows the cushioning material in which the recesses are continuous along the longitudinal direction, and (B) is formed along the short side direction. The buffer material in which the recessed part and convex part which were further formed alternately along the longitudinal direction is shown. FIG. 11A is a cross-sectional view showing a state where the convex portion of the buffer material overlaps with the inter-bump region of the IC chip, and FIG. 11B shows a state where the concave portion of the buffer material overlaps the output bump region of the IC chip. FIG. 12A and 12B are diagrams showing a connection process of an IC chip according to a reference example, FIG. 12A is a plan view showing a mounting surface of the IC chip, and FIG. 12B is a cross-sectional view showing a heat pressing process of the IC chip. It is. FIG. 13 is a cross-sectional view showing a state in which the IC chip is warped so that the area between the bumps is recessed.

  Hereinafter, an electronic component, a connection body, a manufacturing method of a connection body, a connection method of an electronic component, and a buffer material to which the present invention is applied will be described in detail with reference to the drawings. It should be noted that the present invention is not limited to the following embodiments, and various modifications can be made without departing from the scope of the present invention. Further, the drawings are schematic, and the ratio of each dimension may be different from the actual one. Specific dimensions should be determined in consideration of the following description. Moreover, it is a matter of course that portions having different dimensional relationships and ratios are included between the drawings.

[Connector 20]
As shown in FIGS. 1A and 1B, the connection body 20 has the IC chip 1 mounted on the circuit board 10 via an adhesive such as an anisotropic conductive film (ACF) 30, The pressing surface 8 of the IC chip 1 is heated and pressed by the thermocompression bonding tool 40 through the buffer material 15, thereby electrically conducting the bumps provided on the mounting surface 2 of the IC chip 1 and the electrode terminals provided on the circuit board 10. Connected.

[IC chip]
As shown in FIG. 2, the mounting surface 2 connected to the circuit board of the IC chip 1 has a substantially rectangular shape, and along the pair of side edges 2a and 2b facing each other in the length direction, output bumps are formed. An output bump area 4 in which 3 is arranged and an input bump area 6 in which input bumps 5 are arranged are formed. In the IC chip 1, the output bump region 4 is formed on the side edge 2 a side of the mounting surface 2, and the input bump region 6 is formed on the other side edge 2 b side of the mounting surface 2. Thereby, in the IC chip 1, the output bump region 4 and the input bump region 6 are formed apart from each other in the width direction of the mounting surface 2, and the inter-bump region in which no bump is formed at the center of the mounting surface 2. 7 is provided.

  In the output bump area 4, a plurality of output bumps 3 are arranged along the longitudinal direction of the mounting surface 2, so that, for example, three output bump rows 3 </ b> A, 3 </ b> B, and 3 </ b> C are formed sequentially from one side edge 2 a side. Has been. Further, the output bumps 3 of each of the output bump rows 3A to 3C are arranged in a staggered manner.

  Further, in the input bump area 6, for example, an input bump row 5 </ b> A in which a plurality of input bumps 5 are arranged in a row along the longitudinal direction of the mounting surface 2 is formed. The input bump 5 is formed larger than the output bump 3. Thus, in the IC chip 1, the output bump region 4 and the input bump region 6 have an area difference and are disposed asymmetrically on the mounting surface 2. The input / output bumps 3 and 5 may be formed with the same size.

  As the input / output bumps 3 and 5, for example, copper bumps, gold bumps, or copper bumps plated with gold are suitably used. Further, the input / output bumps 3 and 5 are provided in an arrangement corresponding to the input / output terminals provided on the circuit board 10, and the IC chip 1 is aligned and connected to the circuit board 10, thereby providing anisotropy. It is connected to the input / output terminal through the conductive film 30.

  In addition to the arrangement shown in FIG. 2, the input / output bumps 3 and 5 may be arranged in one or more rows on one side edge and in one or more rows on the other side edge. There may be. In addition, the input / output bumps 3 and 5 may have a plurality of rows in one row arrangement, and a portion of the plurality of rows may be one row. Further, the input / output bumps 3 and 5 may be formed in a straight array in which a plurality of rows are parallel and adjacent electrode terminals are parallel, or a plurality of rows of parallel and adjacent electrode terminals are It may be formed in a staggered arrangement that is shifted evenly.

  With recent miniaturization and higher functionality of liquid crystal display devices and other electronic devices, electronic components such as the IC chip 1 are also required to be smaller and lower in height, and the input / output bumps 3 and 5 are also higher in height. Is low (for example, 6 to 15 μm).

[Concave]
Further, the IC chip 1 is provided with a recess 9 that overlaps with an inter-bump region 7 between the output bump region 4 and the input bump region 6 on a pressing surface 8 that is pressed by a crimping tool opposite to the mounting surface 2. ing. The IC chip 1 is provided with the concave portion 9 at a position overlapping with the inter-bump region 7, whereby the pressure of the thermocompression bonding tool 40 is concentrated on the output bump region 4 and the input bump region 6, and warping is suppressed, The output bump 3 and the input bump 5 are sufficiently pressed by the crimping tool 40. Therefore, the IC chip 1 can sufficiently push the conductive particles between the input / output bumps 3 and 5 and the input / output terminals 16 and 17 provided on the circuit board 10 and obtains good electrical conductivity.

  That is, since the inter-bump region 7 is provided between the output bump region 4 and the input bump region 6 in the IC chip 1, when pressure is applied to the entire mounting surface 2 by the thermocompression bonding tool 40, In the output bump region 4 formed in a large area over the width direction by arranging the output bumps 3 in a plurality of rows, the pressing force at the inner edge facing the input bump region 6 is increased, and one of the mounting surfaces 2 The pressure gradient becomes weaker toward the side edge 2a, and the pressing force on the output bumps 3 arranged on one side edge 2a is insufficient. Thereby, there is a possibility that the conduction resistance of the output bump 3 is increased particularly in the outer bump row due to insufficient pushing of the conductive particles.

  Therefore, the IC chip 1 is provided with a recess 9 at a position overlapping the inter-bump area 7 of the pressing surface 8, so that the areas overlapping the output bump area 4 and the input bump area 6 are relatively projected, and the thermocompression bonding tool A pressing force of 40 can be locally received. As a result, the warpage of the IC chip 50 is suppressed, and the pressure gradient in the width direction of the output bump region 4 in which the plurality of output bump rows 3A to 3C are arranged is gently leveled, and on the side edge 2a side. The situation where the pressing force by the thermocompression bonding tool 40 is insufficient is prevented. As a result, the IC chip 1 reliably holds the conductive particles between the output terminals 16 formed on the circuit board 10 even in the outer output bumps 3 formed on the one side edge 2a side. Sex can be secured.

  The concave portion 9 can be formed in, for example, a continuous linear shape by cutting the substrate of the IC chip 1 into a predetermined dimension, for example. Further, as shown in FIG. 3, the recess 9 forms a step between the region overlapping the inter-bump region 7 and the region overlapping the input / output bump region 4, 6 of the circuit board 10 of the IC chip 1. You may form by providing the auxiliary member 11. FIG. The auxiliary member 11 is made of a material different from the substrate of the IC chip 1, for example, a PI film having excellent heat resistance, and is bonded to the substrate 10 by an adhesive member. Further, the auxiliary member 11 may be provided by applying and curing an insulating paste.

  The recess 9 may be formed in any step of the manufacturing process of the IC chip 1. For example, the recess 9 may be formed in advance by cutting the surface of the wafer prior to the step of cutting the IC chip substrate from a large-diameter silicon wafer into pieces. Further, the concave portion 9 may be formed by etching as in the case of a silicon wafer or the like.

[Recess depth D]
When the IC chip 1 is heat-pressed by the thermocompression bonding tool 40, the cushioning material 15 is interposed between the pressing surface 8 and the thermocompression bonding tool 40 (see FIG. 1). The recess 9 formed in the pressing surface 8 preferably has a thickness above T ₁ of the depth D of the buffer material 15 which is interposed between the thermocompression bonding tool 40. Thereby, even when the pressing surface 8 is pressed by the thermocompression bonding tool 40, the IC chip 1 warps so that the inter-bump region 7 is recessed by the buffer material 15 pressing the bottom surface of the recess 9. Can be prevented.

The recess 9 is preferably to a depth within 90% of the substrate thickness T ₂ of the IC chip 1, and more preferably is within 80% depth, even more preferably a depth of up to 70%. In addition, the IC chip 1 preferably has a thickness (T ₂ -D) of a region where the recess 9 is formed of 15 μm or more. If the recess 9 has a depth larger than 90% of the substrate thickness T ₂ of the IC chip 1, a load may be applied to the wiring pattern layer inside the IC chip 1. Further, by setting the concave portion 9 to a depth within 70% of the substrate thickness T ₂ of the IC chip 1, even when the cushioning material 15 presses the bottom surface of the concave portion 9 when the thermocompression bonding tool 40 is pressed, the warp is warped. The suppressing mechanical strength can be maintained.

[Distance between inner edge of output bump and end of recess]
Here, as shown in FIG. 4, the distance between the end of the recess 9 on the output bump region 4 side and the inner edge of the output bump row 3C arranged on the innermost side of the output bump region 4 is C, and the output bump region A is the length in the width direction orthogonal to the arrangement direction of the four output bumps 3. At this time, in the IC chip 1, the end of the recess 9 on the output bump region 4 side has a length A in the width direction of the output bump region 4 from the inner edge of the output bump row 3C toward the one side edge 2a. An area of less than 12.5% (FIG. 4A) and an area of less than 50% of the length A in the width direction of the output bump area 4 from the inner edge of the output bump row 3C toward the other side edge 2b (FIG. 4B) is preferably located between.

  More preferably, in the IC chip 1, the end of the recess 9 on the output bump region 4 side is the length of the output bump region 4 in the width direction from the inner edge of the output bump row 3C toward the one side edge 2a. A region of less than 7.5% of the length A and a region of less than 37.5% of the length A in the width direction of the output bump region 4 from the inner edge of the output bump row 3C toward the other side edge 2b. Located between.

  By forming the recess 9 so that the end on the output bump region 4 side is located in the region, the region overlapping the output bump region 4 is pressed by the thermocompression bonding tool 40 and the region overlapping the inter-bump region 7 Is not pressed excessively. Therefore, the pressure of the thermocompression bonding tool 40 is concentrated on the output bump region 4, warping in the inter-bump region 7 is suppressed, and each output bump row 3 </ b> A to 3 </ b> C can be sufficiently pressed by the thermocompression bonding tool 40.

  In the IC chip 1, the end of the recess 9 on the output bump region 4 side is 12.5 of the length A in the width direction of the output bump region 4 from the inner edge of the output bump row 3 </ b> C toward the one side edge 2 a. When the area exceeding the% is formed, the pressing area by the thermocompression bonding tool 40 in the area overlapping the output bump area 4 is biased toward the one side edge 2a, and the output bump arranged in the innermost side of the output bump area 4 The pressing force for the row 3C is insufficient.

  Further, in the IC chip 1, the end of the recess 9 on the output bump region 4 side has a length A of 50 in the width direction of the output bump region 4 from the inner edge of the output bump row 3C toward the other side edge 2b. When the IC chip 1 is pressed by the thermocompression bonding tool 40, the inside of the output bump area 4 is expanded. Warping occurs so that the central inter-bump region 7 is recessed with the output bump row 3C provided at the center as a fulcrum. Therefore, the pressing force for the output bump row 3A arranged on the outermost side of the output bump region 4 is insufficient.

[Circuit board]
The circuit board 10 is selected according to the use of the connection body 20, and the type thereof is not limited, for example, a glass board, a glass epoxy board, a ceramic board, a flexible board, or the like. The circuit board 10 has input / output terminals 16 and 17 connected to the input / output bumps 3 and 5 provided on the IC chip 1.

[Alignment mark]
Note that the IC chip 1 and the circuit board 10 are provided with an alignment mark (not shown) for aligning the IC chip 1 with the circuit board 10 by being overlapped. As the substrate-side alignment mark and the IC-side alignment mark, various marks that can be aligned with the circuit board 10 and the IC chip 1 can be used. Since the wiring pitch of the input / output terminals of the circuit board 10 and fine pitches of the input / output bumps 3 and 5 of the IC chip 1 are increasing, the IC chip 1 and the circuit board 10 are required to have high-precision alignment adjustment. There are many cases.

[Dummy bump]
Further, as shown in FIG. 5, the IC chip 1 is a so-called dummy bump that is not used for input / output of signals or the like between the output bump area 4 and the input bump area 6 if restrictions on the bump layout and the number of manufacturing steps allow. A dummy bump region 19 in which 18 are arranged may be provided as appropriate.

[adhesive]
Note that an anisotropic conductive film 30 can be suitably used as an adhesive for connecting the IC chip 1 to the circuit board 10. As shown in FIG. 6, the anisotropic conductive film 30 is generally formed by forming a binder resin layer (adhesive layer) 33 containing conductive particles 32 on a release film 31 serving as a base material. As shown in FIG. 1, the anisotropic conductive film 30 has a binder resin layer 33 interposed between the circuit board 10 and the IC chip 1 to connect the circuit board 10 and the IC chip 1. The conductive particles 32 are sandwiched between the output bumps 3 and 5 and the input / output terminals 16 and 17 and are used for conduction.

  The adhesive composition of the binder resin layer 33 is made of a normal binder component containing, for example, a film-forming resin, a thermosetting resin, a latent curing agent, a silane coupling agent, and the like.

  As the film-forming resin, a resin having an average molecular weight of about 10,000 to 80,000 is preferable, and various resins such as an epoxy resin, a modified epoxy resin, a urethane resin, and a phenoxy resin are particularly mentioned. Among these, phenoxy resin is preferable from the viewpoint of film formation state, connection reliability, and the like.

  It does not specifically limit as a thermosetting resin, For example, a commercially available epoxy resin, an acrylic resin, etc. can be used.

  The epoxy resin is not particularly limited. For example, naphthalene type epoxy resin, biphenyl type epoxy resin, phenol novolac type epoxy resin, bisphenol type epoxy resin, stilbene type epoxy resin, triphenolmethane type epoxy resin, phenol aralkyl type epoxy resin. Naphthol type epoxy resin, dicyclopentadiene type epoxy resin, triphenylmethane type epoxy resin and the like. These may be used alone or in combination of two or more.

  There is no restriction | limiting in particular as an acrylic resin, According to the objective, an acrylic compound, liquid acrylate, etc. can be selected suitably. For example, methyl acrylate, ethyl acrylate, isopropyl acrylate, isobutyl acrylate, epoxy acrylate, ethylene glycol diacrylate, diethylene glycol diacrylate, trimethylolpropane triacrylate, dimethylol tricyclodecane diacrylate, tetramethylene glycol tetraacrylate, 2-hydroxy- 1,3-diacryloxypropane, 2,2-bis [4- (acryloxymethoxy) phenyl] propane, 2,2-bis [4- (acryloxyethoxy) phenyl] propane, dicyclopentenyl acrylate, tricyclo Examples include decanyl acrylate, tris (acryloxyethyl) isocyanurate, urethane acrylate, and epoxy acrylate. In addition, what made acrylate the methacrylate can also be used. These may be used individually by 1 type and may use 2 or more types together.

  The latent curing agent is not particularly limited, and examples thereof include a heat curing type curing agent. The latent curing agent does not normally react, but is activated by various triggers selected according to applications such as heat, light, and pressure, and starts the reaction. The activation method of the thermal activation type latent curing agent includes a method of generating active species (cation, anion, radical) by a dissociation reaction by heating, etc., and it is stably dispersed in the epoxy resin near room temperature, and epoxy at high temperature There are a method of initiating a curing reaction by dissolving and dissolving with a resin, a method of initiating a curing reaction by eluting a molecular sieve encapsulated type curing agent at a high temperature, and an elution / curing method using microcapsules. Thermally active latent curing agents include imidazole, hydrazide, boron trifluoride-amine complexes, sulfonium salts, amine imides, polyamine salts, dicyandiamide, etc., and modified products thereof. The above mixture may be sufficient. As the radical polymerization initiator, a known one can be used, and among them, an organic peroxide can be preferably used.

  Although it does not specifically limit as a silane coupling agent, For example, an epoxy type, an amino type, a mercapto sulfide type, a ureido type etc. can be mentioned. By adding the silane coupling agent, the adhesion at the interface between the organic material and the inorganic material is improved.

[Conductive particles]
Examples of the conductive particles 32 contained in the binder resin layer 33 include any known conductive particles used in anisotropic conductive films. That is, as the conductive particles, for example, particles of various metals and metal alloys such as nickel, iron, copper, aluminum, tin, lead, chromium, cobalt, silver, gold, metal oxide, carbon, graphite, glass, ceramic Examples thereof include those in which the surface of particles such as plastic is coated with metal, or those in which the surface of these particles is further coated with an insulating thin film. In the case where the surface of the resin particle is coated with metal, examples of the resin particle include an epoxy resin, a phenol resin, an acrylic resin, an acrylonitrile / styrene (AS) resin, a benzoguanamine resin, a divinylbenzene resin, a styrene resin, and the like. Can be mentioned.

  The adhesive composition constituting the binder resin layer 33 is not limited to the case where it contains a film-forming resin, a thermosetting resin, a latent curing agent, a silane coupling agent, etc. You may make it comprise from any material used as an adhesive composition of a film.

  The release film 31 that supports the binder resin layer 33 is made of, for example, a release agent such as silicone on PET (Poly Ethylene Terephthalate), OPP (Oriented Polypropylene), PMP (Poly-4-methylpentene-1), PTFE (Polytetrafluoroethylene), and the like. It is applied to prevent the anisotropic conductive film 30 from drying and maintain the shape of the anisotropic conductive film 30.

  The anisotropic conductive film 30 may be produced by any method, but can be produced, for example, by the following method. An adhesive composition containing a film-forming resin, a thermosetting resin, a latent curing agent, a silane coupling agent, conductive particles and the like is prepared. The anisotropic conductive film 30 in which the binder resin layer 33 is supported on the release film 31 by applying the adjusted adhesive composition onto the release film 31 using a bar coater, a coating apparatus, and the like, and drying it with an oven or the like. Get.

  Moreover, in the above-mentioned embodiment, although the adhesive film which shape | molded the thermosetting resin composition which contained the electroconductive particle 32 in the binder resin layer 33 suitably as an adhesive was demonstrated to the example as an adhesive agent, it is set to this invention. The adhesive is not limited to this, and may be, for example, an insulating adhesive film including only the binder resin layer 33. In addition, the adhesive according to the present invention has a configuration in which an insulating adhesive layer made of only the binder resin layer 33 and a conductive particle-containing layer made of the binder resin layer 33 containing the conductive particles 32 are laminated. it can. Further, the adhesive is not limited to such an adhesive film formed into a film, but is an insulating adhesive composed only of a conductive adhesive paste in which conductive particles 32 are dispersed in a binder resin composition or a binder resin composition. It may be a paste. The adhesive according to the present invention includes any of the forms described above.

[Connection process]
Next, a connection process for connecting the IC chip 1 to the circuit board 10 will be described. First, the anisotropic conductive film 30 is temporarily attached on the mounting surface on which the input / output terminals of the circuit board 10 are formed. Next, the circuit board 10 is placed on the stage of the connection device, and the IC chip 1 is placed on the mounting surface of the circuit board 10 via the anisotropic conductive film 30.

  Next, the thermocompression bonding tool 40 heated to a predetermined temperature for curing the binder resin layer 33 is heat-pressed on the pressing surface 8 of the IC chip 1 through the buffer material 15 at a predetermined pressure and time. Thereby, the binder resin layer 33 of the anisotropic conductive film 30 exhibits fluidity and flows out from between the mounting surface 2 of the IC chip 1 and the mounting surface of the circuit board 10, and the conductive particles in the binder resin layer 33. 32 is clamped between the output bump 3 and the output terminal 16 and between the input bump 5 and the input terminal 17.

  At this time, according to the IC chip 1 to which the present invention is applied, since the concave portion 9 is provided on the pressing surface 8 so as to overlap the inter-bump region 7, the pressure of the thermocompression bonding tool 40 is applied to the output bump region 4 and the input bump. Concentrating on the region 6, curling is suppressed, and the output bump 3 and the input bump 5 are sufficiently pressed by the thermocompression bonding tool 40.

  As a result, the conductive particles 32 are electrically connected between the input / output bumps 3 and 5 and the input / output terminals 16 and 17 of the circuit board 10 and are heated by the thermocompression bonding tool 40 in this state. The binder resin is cured. Therefore, the IC chip 1 can reliably ensure electrical continuity with the output terminal 16 formed on the circuit board 10 also in the output bump row 3A on the side edge 2a side.

  The conductive particles 32 that are not between the input / output bumps 3 and 5 and the input / output terminals 16 and 17 of the circuit board 10 are dispersed in the binder resin and maintain an electrically insulated state. As a result, electrical conduction is achieved only between the output bumps 3 and the input bumps 5 of the IC chip 1 and the input / output terminals 16 and 17 of the circuit board 10. In addition, by using a fast curing type radical polymerization reaction system as the binder resin, the binder resin can be rapidly cured even with a short heating time. In addition, the anisotropic conductive film 30 is not limited to the thermosetting type, and may be a photo-curing type or a photo-heat combined type adhesive as long as pressure connection is performed.

Next, examples of the present invention will be described. In this embodiment, the depth D of the recess formed on the pressing surface of the IC chip, the distance C between the end of the recess on the output bump area side and the inner edge of the output bump array arranged on the innermost side of the output bump area, the distance between the inner edge of the input bump region side end portion and the input bump region sequence input bump rows of recesses J, and by changing the thickness T ₁ of the buffer material to form a connection body samples, inside the output bumps column The deformation amount of the conductive particles in the outer output bump row was measured and evaluated (see FIGS. 1 and 4).

[IC chip for evaluation]
The IC chip used in this example has a size of 20 mm × 1.5 mm and a maximum substrate thickness of 160 μm, and an output bump area in which output bumps are arranged along the longitudinal direction is provided on one side edge of the mounting surface. An input bump region in which input bumps are arranged along the longitudinal direction is formed on the other side edge. Three output bump rows are arranged in parallel in the width direction of the mounting surface in the output bump region, and one input bump row is formed in the input bump region. The length A in the width direction of the output bump region was 400 μm, and the length in the width direction of the input bump region was 140 μm. The output bumps constituting the three output bump rows are arranged in a staggered pattern (see FIG. 2). The width of the inter-bump area between the output bump area and the input bump area is 800 μm.

[Evaluation board]
The circuit board on which the IC chip for evaluation is mounted is a glass substrate having a thickness of 200 μm, and an Al layer is formed by so-called solid wiring on the mounting surface.

[Buffer material / anisotropic conductive film]
The IC chip is mounted by sticking the anisotropic conductive film on the mounting surface of the glass substrate, and then heat-pressing the pressing surface of the IC chip with a thermocompression bonding tool through the buffer material at a predetermined temperature, pressure, and time. went. Teflon (registered trademark) was used as a buffer material, and thicknesses of 50 μm and 100 μm were prepared.

  The anisotropic conductive film is of an epoxy thermosetting type, 25 parts by mass of phenoxy resin (PKHH, manufactured by Sakai Kogyo Co., Ltd.), 10 parts by mass of epoxy resin (EP828, manufactured by Mitsubishi Chemical Corporation), and cationic curing. Agent (SI-60L, manufactured by Sanshin Chemical Industry Co., Ltd.) 10 parts by mass, silane coupling agent (A-187, manufactured by Momentive Performance Materials) 2 parts by mass, conductive particles (AUL703, Sekisui Chemical Co., Ltd.) 30 parts by mass of metal-coated resin particles having an Ni / Au plating film formed on the surface of the acrylic resin particles and an average particle diameter of 3.0 μm were mixed using a stirrer. It was produced by applying and drying on a PET film having been subjected to a release treatment to the blended mixture so that the average thickness after drying was 10 μm. Moreover, the pressure bonding conditions of the IC chip with the thermocompression bonding tool were 150 ° C., 90 MPa, and 5 seconds.

[First embodiment]
In the first embodiment, a connection sample is formed in which the distances C and J between the end of the recess and the inner edge of the input / output bump row are constant, and the depth D of the recess is changed with respect to the thickness of the buffer material. The diameters of the conductive particles that were compressed and deformed were measured in the output bump row and the inner output bump row. And the case where the conductive particle diameter after deformation in both output bump rows is 2.4 μm or less, the conductive particle diameter after deformation in one or both output bump rows is larger than 2.4 μm and 2.6 μm or less. The case was marked with ◯, and the case where the conductive particle diameter after deformation in one or both of the output bump rows was 2.7 μm or more was marked with ×.

[Example 1]
In Example 1, the recess depth D was 50 μm, the distance C between the inner edge of the innermost output bump row and the end of the recess, and the distance J between the inner edge of the input bump row and the end of the recess were 50 μm. (FIG. 4B). A buffer material having a thickness of 50 μm was used.

  In the connection sample according to Example 1, the conductive particle diameter in the outer output bump row was 2.6 μm, and the conductive particle diameter in the inner output bump row was 2.2 μm.

[Example 2]
In Example 2, the recess depth D was 60 μm, the distance C between the inner edge of the innermost output bump row and the end of the recess, and the distance J between the inner edge of the input bump row and the end of the recess were 50 μm. (FIG. 4B). A buffer material having a thickness of 50 μm was used.

  In the connection body sample according to Example 2, the conductive particle diameter in the outer output bump row was 2.4 μm, and the conductive particle diameter in the inner output bump row was 2.2 μm.

[Example 3]
In Example 3, the recess depth D was 100 μm, the distance C between the inner edge of the innermost output bump row and the end of the recess, and the distance J between the inner edge of the input bump row and the end of the recess were 50 μm. (FIG. 4B). A buffer material having a thickness of 100 μm was used.

  In the connection body sample according to Example 3, the conductive particle diameter in the outer output bump row was 2.5 μm, and the conductive particle diameter in the inner output bump row was 2.2 μm.

[Example 4]
In Example 4, the recess depth D was 110 μm, the distance C between the inner edge of the innermost output bump row and the end of the recess, and the distance J between the inner edge of the input bump row and the end of the recess were 50 μm. (FIG. 4B). A buffer material having a thickness of 100 μm was used.

  In the connection body sample according to Example 4, the conductive particle diameter in the outer output bump row was 2.3 μm, and the conductive particle diameter in the inner output bump row was 2.2 μm.

[Comparative Example 1]
In Comparative Example 1, no recess was provided on the pressing surface of the IC chip. A buffer material having a thickness of 50 μm was used.

  In the connection body sample according to Comparative Example 1, the conductive particle diameter in the outer output bump array was 2.8 μm, and the conductive particle diameter in the inner output bump array was 2.1 μm.

[Comparative Example 2]
In Comparative Example 2, the recess depth D was 40 μm, the distance C between the inner edge of the innermost output bump row and the end of the recess, and the distance J between the inner edge of the input bump row and the end of the recess were 50 μm. (FIG. 4B). A buffer material having a thickness of 50 μm was used.

  In the connection body sample according to Comparative Example 2, the conductive particle diameter in the outer output bump array was 2.7 μm, and the conductive particle diameter in the inner output bump array was 2.3 μm.

[Comparative Example 3]
In Comparative Example 3, the recess depth D was 90 μm, the distance C between the inner edge of the innermost output bump row and the end of the recess, and the distance J between the inner edge of the input bump row and the end of the recess were 50 μm. (FIG. 4B). A buffer material having a thickness of 100 μm was used.

  In the connection body sample according to Comparative Example 3, the conductive particle diameter in the outer output bump row was 2.8 μm, and the conductive particle diameter in the inner output bump row was 2.2 μm.

  As shown in Table 1, since the IC chip according to Examples 1 to 4 has a depth equal to or greater than the thickness of the cushioning material, the depth D of the recess is also pressed when the pressing surface is pressed by the thermocompression bonding tool. It was possible to prevent the warping from occurring so that the area between the bumps was recessed without the buffer material pressing the bottom surface of the recess. Therefore, the connection body samples according to Examples 1 to 4 have good conductive properties because the conductive particle diameter after compression deformation is 2.6 μm or less even in the outer output bump row.

  On the other hand, since the concave portion is not provided in Comparative Example 1, in Comparative Examples 2 and 3, since the concave portion depth D is less than the thickness of the buffer material, the pressing of the thermocompression bonding tool through the buffer material is performed. The pressure was transmitted to the inter-bump region, and warping occurred so that the inter-bump region was recessed with the inner edges of the input bump row and the inner output bump row as fulcrums. Therefore, the connection body samples according to Comparative Examples 1 to 3 are insufficient in pressing force by the thermocompression bonding tool in the outer output bump row, and the conductive particle diameter after compression deformation becomes 2.7 μm or more, which may cause poor conduction. Occurred.

[Second Embodiment]
In the second embodiment, a connection sample is formed by changing the distances C and J between the end of the recess and the inner edge of the input / output bump row, and the outer output bump row and the inner output bump row are compressed and deformed. The diameter of the conductive particles formed was measured. The evaluation of the conductive particle diameter after compression deformation is the same as in the first example.

[Example 5]
In Example 5, the recess depth D is 60 μm, the distance C between the inner edge of the innermost output bump row and the end of the recess, and the distance J between the inner edge of the input bump row and the end of the recess is −30 μm. did. That is, the IC chip according to Example 5 is formed up to a position where the end of the recess overlaps with the input / output bump region by 30 μm (FIG. 4A). This is a position of 7.5% toward one side edge side of the length A (400 μm) in the width direction of the output bump region. A buffer material having a thickness of 50 μm was used.

  In the connection body sample according to Example 5, the conductive particle diameter in the outer output bump row was 2.2 μm, and the conductive particle diameter in the inner output bump row was 2.5 μm.

[Example 6]
In Example 6, the recess depth D is 60 μm, the distance C between the inner edge of the innermost output bump row and the end of the recess, and the distance J between the inner edge of the input bump row and the end of the recess is −20 μm. did. That is, the IC chip according to Example 6 is formed up to a position where the end of the recess overlaps with the input / output bump region by 20 μm (FIG. 4A). This is a position of 5% toward one side edge of the length A (400 μm) in the width direction of the output bump region. A buffer material having a thickness of 50 μm was used.

  In the connection body sample according to Example 6, the conductive particle diameter in the outer output bump row was 2.2 μm, and the conductive particle diameter in the inner output bump row was 2.3 μm.

[Example 7]
In Example 7, the recess depth D was 60 μm, the distance C between the inner edge of the innermost output bump row and the end of the recess, and the distance J between the inner edge of the input bump row and the end of the recess were 0 μm. . That is, the IC chip according to Example 7 is formed up to the position where the end of the recess overlaps the inner edge of the input / output bump region. This is a position of 0% toward one side edge of the length A (400 μm) in the width direction of the output bump region. A buffer material having a thickness of 50 μm was used.

  In the connection body sample according to Example 7, the conductive particle diameter in the outer output bump row was 2.1 μm, and the conductive particle diameter in the inner output bump row was 2.0 μm.

[Example 8]
In Example 8, the recess depth D was 60 μm, the distance C between the inner edge of the innermost output bump row and the end of the recess, and the distance J between the inner edge of the input bump row and the end of the recess were 50 μm. (FIG. 4B). This is a position of 12.5% toward the other side edge of the length A (400 μm) in the width direction of the output bump region. A buffer material having a thickness of 50 μm was used.

  In the connection body sample according to Example 8, the conductive particle diameter in the outer output bump row was 2.4 μm, and the conductive particle diameter in the inner output bump row was 2.2 μm.

[Example 9]
In Example 9, the recess depth D was 60 μm, the distance C between the inner edge of the innermost output bump row and the end of the recess, and the distance J between the inner edge of the input bump row and the end of the recess were 100 μm. (FIG. 4B). This is a position of 25% toward the other side edge side of the length A (400 μm) in the width direction of the output bump region. A buffer material having a thickness of 50 μm was used.

  In the connection body sample according to Example 9, the conductive particle diameter in the outer output bump row was 2.5 μm, and the conductive particle diameter in the inner output bump row was 2.3 μm.

[Example 10]
In Example 10, the recess depth D was 60 μm, the distance C between the inner edge of the innermost output bump row and the end of the recess, and the distance J between the inner edge of the input bump row and the end of the recess were 150 μm. (FIG. 4B). This is a position of 37.5% toward the other side edge side of the length A (400 μm) in the width direction of the output bump region. A buffer material having a thickness of 50 μm was used.

  In the connection body sample according to Example 10, the conductive particle diameter in the outer output bump row was 2.6 μm, and the conductive particle diameter in the inner output bump row was 2.1 μm.

[Comparative Example 4]
In Comparative Example 4, the recess depth D is 60 μm, the distance C between the inner edge of the innermost output bump row and the end of the recess, and the distance J between the inner edge of the input bump row and the end of the recess is −50 μm. did. That is, the IC chip according to Comparative Example 4 is formed up to a position where the end of the recess overlaps with the input / output bump region by 50 μm (FIG. 4A). This is at a position of 12.5% toward one side edge of the length A (400 μm) in the width direction of the output bump region. A buffer material having a thickness of 50 μm was used.

  In the connection body sample according to Comparative Example 4, the conductive particle diameter in the outer output bump row was 2.2 μm, and the conductive particle diameter in the inner output bump row was 2.7 μm.

[Comparative Example 5]
In Comparative Example 5, the recess depth D was 60 μm, the distance C between the inner edge of the innermost output bump row and the end of the recess, and the distance J between the inner edge of the input bump row and the end of the recess were 200 μm. (FIG. 4B). This is a position of 50% toward the other side edge of the length A (400 μm) in the width direction of the output bump region. A buffer material having a thickness of 50 μm was used.

  In the connection body sample according to Comparative Example 5, the conductive particle diameter in the outer output bump row was 2.8 μm, and the conductive particle diameter in the inner output bump row was 2.2 μm.

  As shown in Table 2, in the IC chips according to Examples 5 to 10, the output bump region side end portion of the recess has the output bump region side from the inner edge of the innermost output bump row toward one side edge side. A region of less than 12.5% of the length A in the width direction, and a region of less than 50% of the length A in the width direction of the output bump region from the inner edge of the innermost output bump row toward the other side edge side; Is located between. Therefore, in the connection body samples according to Examples 5 to 10, the region overlapping the output bump region is pressed by the thermocompression bonding tool via the cushioning material, and the region overlapping the inter-bump region is excessively pressed. Nor. Therefore, the pressure of the thermocompression bonding tool concentrates on the output bump region, and warpage in the inter-bump region is suppressed, and the outer and inner output bump rows can be sufficiently pressed by the thermocompression bonding tool. Therefore, the connection body samples according to Examples 5 to 10 have good conductive properties because the conductive particle diameter after compression deformation is 2.6 μm or less even in the outer output bump row.

  On the other hand, in the IC chip according to Comparative Example 4, the end of the concave portion on the output bump region side has the length A in the width direction of the output bump region from the inner edge of the innermost output bump row toward one side edge side. Since the concave portion is formed up to the position of 12.5%, the pressing area by the thermocompression bonding tool in the area overlapping the output bump area is biased to one side edge side, and the output bump arranged in the innermost side of the output bump area The pressing force on the row is insufficient. For this reason, in the connection body sample according to Comparative Example 4, the pressing force by the thermocompression bonding tool is insufficient in the inner output bump row, and the conductive particle diameter after compression deformation becomes 2.7 μm, which may cause poor conduction. .

  In addition, in the IC chip according to Comparative Example 5, the end of the concave portion on the output bump region side has the length A in the width direction of the output bump region from the inner edge of the innermost output bump row to the other side edge side. Since the recess is formed up to 50% of the position, the pressing force of the thermocompression bonding tool is transmitted to the inter-bump area via the cushioning material, and the inter-bump area using the inner edges of the input bump array and the inner output bump array as fulcrums Warpage occurred to dent. For this reason, the connected body sample according to Comparative Example 5 lacks the pressing force by the thermocompression bonding tool in the outer output bump row, and the conductive particle diameter after compression deformation becomes 2.7 μm or more, which may cause poor conduction. It was.

[Third embodiment]
In the third embodiment, the distance C between the end of the concave portion on the output bump area side and the inner edge of the output bump row, and the distance J between the end of the concave portion on the input bump region side and the inner edge of the input bump row, A connected body sample with different diameters was formed, and the diameters of the conductive particles subjected to compression deformation were measured in the outer output bump row and the inner output bump row. The evaluation of the conductive particle diameter after compression deformation is the same as in the first example.

[Example 11]
In the IC chip according to Example 11, the recess depth D was 60 μm, and the distance C between the inner edge of the innermost output bump row and the end of the recess on the output bump region side was −30 μm. That is, the end of the concave portion on the output bump area side is formed to a position where it overlaps with the output bump area by 30 μm. This is a position of 7.5% toward one side edge side of the length A (400 μm) in the width direction of the output bump region. In the IC chip according to Example 11, the distance J between the inner edge of the input bump row and the end of the concave portion on the input bump area side was 150 μm. A buffer material having a thickness of 50 μm was used.

  In the connection body sample according to Example 11, the conductive particle diameter in the outer output bump row was 2.3 μm, and the conductive particle diameter in the inner output bump row was 2.6 μm.

[Example 12]
The IC chip according to Example 12 had a recess depth D of 60 μm, and a distance C between the inner edge of the innermost output bump row and the end of the recess on the output bump region side was −20 μm. That is, the end of the concave portion on the output bump region side is formed up to a position where it overlaps with the output bump region by 20 μm. This is a position of 5% toward one side edge of the length A (400 μm) in the width direction of the output bump region. In the IC chip according to Example 12, the distance J between the inner edge of the input bump row and the end of the concave portion on the input bump region side was 50 μm. A buffer material having a thickness of 50 μm was used.

  In the connection body sample according to Example 12, the conductive particle diameter in the outer output bump row was 2.3 μm, and the conductive particle diameter in the inner output bump row was 2.4 μm.

[Example 13]
In the IC chip according to Example 13, the recess depth D was 60 μm, and the distance C between the inner edge of the innermost output bump row and the end of the recess on the output bump region side was 50 μm. This is a position of 12.5% toward the other side edge of the length A (400 μm) in the width direction of the output bump region. In the IC chip according to Example 13, the distance J between the inner edge of the input bump row and the end of the concave portion on the input bump region side was set to −20 μm. That is, the end of the concave portion on the input bump area side is formed to a position where it overlaps with the input bump area by 20 μm. A buffer material having a thickness of 50 μm was used.

  In the connection body sample according to Example 13, the conductive particle diameter in the outer output bump row was 2.4 μm, and the conductive particle diameter in the inner output bump row was 2.2 μm.

[Example 14]
In the IC chip according to Example 14, the recess depth D was 60 μm, and the distance C between the inner edge of the innermost output bump row and the end of the recess on the output bump region side was 150 μm. This is a position of 37.5% toward the other side edge side of the length A (400 μm) in the width direction of the output bump region. In the IC chip according to Example 14, the distance J between the inner edge of the input bump row and the end of the concave portion on the input bump region side was set to −30 μm. That is, the end of the concave portion on the input bump area side is formed to a position where it overlaps with the input bump area by 30 μm. A buffer material having a thickness of 50 μm was used.

  In the connection body sample according to Example 14, the conductive particle diameter in the outer output bump row was 2.6 μm, and the conductive particle diameter in the inner output bump row was 2.2 μm.

[Comparative Example 6]
In the IC chip according to Comparative Example 6, the recess depth D was 60 μm, and the distance C between the inner edge of the innermost output bump row and the end of the recess on the output bump region side was −50 μm. That is, the end of the concave portion on the output bump area side is formed to a position where it overlaps with the output bump area by 50 μm. This is at a position of 12.5% toward one side edge of the length A (400 μm) in the width direction of the output bump region. In the IC chip according to Comparative Example 6, the distance J between the inner edge of the input bump row and the end of the concave portion on the input bump region side was 200 μm. A buffer material having a thickness of 50 μm was used.

  In the connection sample according to Comparative Example 6, the conductive particle diameter in the outer output bump array was 2.2 μm, and the conductive particle diameter in the inner output bump array was 2.7 μm.

[Comparative Example 7]
In the IC chip according to Comparative Example 7, the recess depth D was 60 μm, and the distance C between the inner edge of the innermost output bump row and the end of the recess on the output bump region side was 200 μm. This is a position of 50% toward the other side edge of the length A (400 μm) in the width direction of the output bump region. In the IC chip according to Comparative Example 7, the distance J between the inner edge of the input bump row and the end of the concave portion on the input bump region side was set to −50 μm. That is, the end of the concave portion on the input bump area side is formed to a position where it overlaps with the input bump area by 50 μm. A buffer material having a thickness of 50 μm was used.

  In the connection body sample according to Comparative Example 7, the conductive particle diameter in the outer output bump array was 2.8 μm, and the conductive particle diameter in the inner output bump array was 2.1 μm.

  As shown in Table 3, in the IC chips according to Examples 11 to 14, the output bump region side end portion of the recess has the output bump region side of the innermost output bump row 3 toward the one side edge side. A region of less than 12.5% of the length A in the width direction, and a region of less than 50% of the length A in the width direction of the output bump region from the inner edge of the innermost output bump row toward the other side edge side; Is located between. Therefore, the connected body samples according to Examples 11 to 14 are output by the thermocompression bonding tool via the cushioning material as in Examples 5 to 10 described above, regardless of the position of the end of the concave portion on the input bump region side. The area overlapping the bump area is pressed, and the area overlapping the inter-bump area is not excessively pressed. Therefore, the pressure of the thermocompression bonding tool concentrates on the output bump region, and warpage in the inter-bump region is suppressed, and the outer and inner output bump rows can be sufficiently pressed by the thermocompression bonding tool. Therefore, the connection body samples according to Examples 11 to 14 have good conductive properties because the conductive particle diameter after compression deformation is 2.6 μm or less even in the outer output bump row.

  On the other hand, in the IC chip according to Comparative Example 6, the end of the concave portion on the output bump region side has the length A in the width direction of the output bump region from the inner edge of the innermost output bump row toward one side edge side. Since the concave portion is formed up to the position of 12.5%, the pressing area by the thermocompression bonding tool in the area overlapping the output bump area is biased to one side edge side, and the output bump arranged in the innermost side of the output bump area The pressing force on the row is insufficient. Therefore, in the connection body sample according to Comparative Example 6, the pressing force by the thermocompression bonding tool is insufficient in the inner output bump row, and the conductive particle diameter after compression deformation becomes 2.7 μm, which may cause conduction failure. .

Further, in the IC chip according to Comparative Example 7, the end portion of the concave portion on the output bump region side has the length A in the width direction of the output bump region from the inner edge of the innermost output bump row to the other side edge side. Since the recess is formed up to 50% of the position, the pressing force of the thermocompression bonding tool is transmitted to the inter-bump area via the cushioning material, and the inter-bump area using the inner edges of the input bump array and the inner output bump array as fulcrums Warpage occurred to dent. For this reason, in the connection body sample according to Comparative Example 7, the pressing force by the thermocompression bonding tool is insufficient in the outer output bump row, the conductive particle diameter after compression deformation becomes 2.7 μm or more, and there is a risk of poor conduction. It was.
[Modification of cushioning material]

  Next, a second embodiment of the present invention will be described. In the following description, the same components as those of the IC chip 1, the circuit board 10, and the connection body 20 described above are denoted by the same reference numerals and the details thereof are omitted.

  In the present invention, the recess 42 may be provided in the cushioning material 41 without providing the recess 9 in the pressing surface 8 of the IC chip 1. The buffer material 41 is interposed between the pressing surface 8 of the IC chip 1 and the thermocompression bonding tool 40 when the IC chip 1 is anisotropically conductively connected to the circuit board 10 in the same manner as the buffer material 15 described above. It is.

  As shown in FIG. 7A, the cushioning material 41 has a recess 42 that overlaps the inter-bump region 7 between the output bump region 4 and the input bump region 6 on the surface to be in close contact with the pressing surface 8 of the IC chip 1. Is provided. As shown in FIG. 8, the cushioning material 41 is formed in a rectangular shape, and convex portions 43 that overlap with the input / output bump regions 4 and 6 of the IC chip 1 are formed in the longitudinal direction on both sides in the width direction. A recess 42 that overlaps the inter-bump region 7 is formed between the portions 43 in the longitudinal direction.

  The buffer material 41 is provided with a concave portion 42 at a position overlapping with the inter-bump region 7, so that the convex portion 43 overlapping with the output bump region 4 and the input bump region 6 is relatively projected. Can be conveyed locally.

  Thereby, the buffer material 41 concentrates the pressure of the thermocompression bonding tool 40 on the output bump region 4 and the input bump region 6 to suppress the warp of the IC chip 1, and the plurality of output bump rows 3A to 3C are arranged. Further, the pressure gradient in the width direction of the output bump region 4 is gently leveled, and a situation in which the pressing force by the thermocompression bonding tool 40 is insufficient on the one side edge 2a side is prevented. Therefore, the IC chip 1 reliably holds the conductive particles between the output terminal 16 formed on the circuit board 10 even in the outer output bump 3 formed on the one side edge 2a side. Can be secured.

  In this way, by interposing the buffer material 41 having the recesses 42 formed thereon, the IC chip 1 is sufficiently pressed against the output bumps 3 and the input bumps 5 by the thermocompression bonding tool 40, and the input / output bumps 3 and 5 and the circuit are connected. Conductive particles can be sufficiently pushed between the input / output terminals 16 and 17 provided on the substrate 10 to obtain good electrical conductivity.

  The buffer material 41 having the recesses 42 can be manufactured using a known material that is generally used as a buffer material at the time of connection using an anisotropic conductive film, such as polyimide, silicone rubber, polytetrafluoroethylene, etc. For example, it can be manufactured by injection molding or extrusion molding.

  Moreover, the buffer material 41 can form the recessed part 42 by cutting the surface. Further, as shown in FIG. 9, the buffer material 41 is provided with an auxiliary member 44 that forms a step between the area overlapping the inter-bump area 7 and the area overlapping the input / output bump areas 4 and 6. It may be formed. The auxiliary member 44 is made of a material that can be used for the buffer material 41, for example, a PI film having excellent heat resistance, and is bonded to the buffer material 41 by an adhesive member. Further, the auxiliary member 44 may be provided by applying and curing an insulating paste. In practice, the cushioning material 41 is preferably a single member. This is because anisotropic connection is performed continuously, so that it is easier to have the same condition than a combination of a plurality of members.

  As shown in FIG. 10A, the cushioning material 41 in which the concave portions 42 and the convex portions 43 are formed is formed in a film shape, and the concave portions 42 are continuous along the longitudinal direction. Or As shown in FIG. 10B, the buffer material 41 is formed in a film shape, and the concave portions 42 and the convex portions 43 formed along the short direction are alternately formed along the longitudinal direction. Then, the buffer material 41 is wound and stored in a roll shape, pulled out from the roll body in the manufacturing process of the connection body 20, and disposed between the thermocompression bonding tool and the IC chip 1 or the anisotropic conductive film 30. Used.

[Recess depth D]
The recess 42 preferably has a depth D ₁ that is 25% or more of the total thickness T ₃ of the cushioning material 41. Thereby, even when the buffer material 41 is pressed by the thermocompression bonding tool 40, the concave portion 42 does not press the pressing surface 8, and the IC chip 1 is prevented from warping so that the inter-bump region 7 is recessed. can do.

On the other hand, when the depth D ₁ of the recess 42 is less than 25% of the total thickness T ₃ of the buffer material 41, the cushioning material 41, the pressing surface 8 is bent recess 42 when pressed by the thermocompression bonding tool 40 The IC chip 1 may be warped so that the inter-bump region 7 is recessed due to the contact, and the pressing force of the thermocompression bonding tool 40 is transmitted to the inter-bump region. For this reason, the IC chip 1 may be insufficiently pressed by the thermocompression bonding tool 40 in the outer output bump row, resulting in poor conduction.

[Distance between inner edge of output bump and end of recess]
Here, the distance between the end of the recess 42 on the output bump region 4 side and the inner edge of the output bump row 3C arranged on the innermost side of the output bump region 4 is C ′, and the output bump 3 of the output bump region 4 Let A be the length in the width direction orthogonal to the arrangement direction. At this time, as shown in FIG. 11A, in the buffer material 41, the end of the concave portion 42 on the input / output bump region 4 side is located in the inter-bump region, and the convex portion 43 and the inter-bump region overlap. It is preferable to set the range to be up to 50% (25% on each side) of the width G of the inter-bump region. Further, as shown in FIG. 11B, the buffer material 41 has an output bump region in which the end of the recess 42 on the output bump region 4 side is directed from the inner edge of the output bump row 3C toward the one side edge 2a. 4 is preferably located in a region of less than 20% of the length A in the width direction.

  By disposing the recess 42 so that the end on the output bump region 4 side is located in the region, the region overlapping the output bump region 4 is pressed with sufficient pressure by the thermocompression bonding tool 40, and the inter-bump region 7 The region that overlaps is not excessively pressed. Therefore, the pressure of the thermocompression bonding tool 40 is concentrated on the output bump region 4, warping in the inter-bump region 7 is suppressed, and each output bump row 3 </ b> A to 3 </ b> C can be sufficiently pressed by the thermocompression bonding tool 40.

  In the buffer material 41, the end of the concave portion 42 on the input / output bump region 4 side is located from the center of the inter-bump region, and the range in which the convex portion 43 and the inter-bump region overlap is 50% of the width G of the inter-bump region. If the IC chip 1 is pressed by the thermocompression bonding tool 40, the output bumps provided inside the output bump area 4 are spread. Warping occurs so that the central inter-bump region 7 is recessed with the row 3C as a fulcrum. Therefore, the pressing force for the output bump row 3A arranged on the outermost side of the output bump region 4 is insufficient.

  Further, in the buffer material 41, the end of the recess 42 on the output bump region 4 side has a length A of 20 in the width direction of the output bump region 4 from the inner edge of the output bump row 3C toward the one side edge 2a. %, The pressure area by the thermocompression bonding tool 40 in the area overlapping the output bump area 4 is biased toward the one side edge 2a, and the output bump arranged in the innermost side of the output bump area 4 The pressing force for the row 3C is insufficient.

[Connection process]
Next, a connection process in which the IC chip 1 is anisotropically conductively connected to the circuit board 10 using the buffer material 41 will be described. First, the buffer material 41 is transported between the pressing surface 8 of the IC chip 1 and a thermocompression bonding tool (not shown) heated to a low temperature for temporary attachment, and the input / output terminals of the circuit board 10 are formed. An anisotropic conductive film 30 is temporarily attached on the surface. Next, the circuit board 10 is placed on the stage of the connection device, and the IC chip 1 is placed on the mounting surface of the circuit board 10 via the anisotropic conductive film 30.

  Next, the thermocompression bonding tool 40 heated to a predetermined temperature for curing the binder resin layer 33 is heat-pressed on the pressing surface 8 of the IC chip 1 through the buffer material 41 at a predetermined pressure and time. Thereby, the binder resin layer 33 of the anisotropic conductive film 30 exhibits fluidity and flows out from between the mounting surface 2 of the IC chip 1 and the mounting surface of the circuit board 10, and the conductive particles in the binder resin layer 33. 32 is clamped between the output bump 3 and the output terminal 16 and between the input bump 5 and the input terminal 17.

Here, as described above, the cushioning material 41 is formed in a film shape, pulled out from the roll body, and is used by being transported below the thermocompression bonding tool. At this time, when the conveying direction P ₂ the transport direction P ₁ and the circuit board anisotropic conductive film 30 and the IC chip 1 is mounted in the cushioning material 41 is the same, as shown in FIG. 10 (A), longitudinal The buffer material 41 in which the recessed part 42 continues along is used. In this case, since the buffer material 41 is conveyed in parallel with the anisotropic conductive film 30, it can be arrange | positioned by the method similar to a normal anisotropic conductive connection.

Further, when the conveying direction P ₂ the transport direction P ₁ and the circuit board anisotropic conductive film 30 and the IC chip 1 is mounted in the cushioning material 41 are orthogonal, as shown in FIG. 10 (B), the short A cushioning material 41 in which concave portions 42 and convex portions 43 formed along the direction are alternately formed along the longitudinal direction is used.

  According to the buffer material 41 to which the present invention is applied, the concave portion 42 is provided so as to overlap with the inter-bump region 7 of the IC chip 1, so that the pressure of the thermocompression bonding tool 40 causes the output bump region 4, the input bump region 6, and the like. The output bumps 3 and the input bumps 5 are sufficiently pressed by the thermocompression bonding tool 40.

  As a result, the conductive particles 32 are electrically connected between the input / output bumps 3 and 5 and the input / output terminals 16 and 17 of the circuit board 10 and are heated by the thermocompression bonding tool 40 in this state. The binder resin is cured. Therefore, the IC chip 1 can reliably ensure electrical continuity with the output terminal 16 formed on the circuit board 10 also in the output bump row 3A on the side edge 2a side.

  The conductive particles 32 that are not between the input / output bumps 3 and 5 and the input / output terminals 16 and 17 of the circuit board 10 are dispersed in the binder resin and maintain an electrically insulated state. As a result, electrical conduction is achieved only between the output bumps 3 and the input bumps 5 of the IC chip 1 and the input / output terminals 16 and 17 of the circuit board 10.

[Fourth embodiment]
In the fourth embodiment, the IC chip is connected to the glass substrate by using the cushioning material in which the recess depth D ₁ and the distances C ′ and J ′ between the end of the recess and the inner edge of the input / output bump row are changed. The connected body sample was formed, and the diameter of the conductive particles subjected to compression deformation was measured in the outer output bump row and the inner output bump row. The evaluation of the conductive particle diameter after compression deformation is the same as in the first example.

[IC chip for evaluation]
The IC chip used in this example has a size of 20 mm × 1.6 mm and a thickness of 0.2 mm, and an output bump area in which output bumps are arranged along the longitudinal direction is provided on one side edge of the mounting surface. On the other side edge, an input bump area in which input bumps are arranged along the longitudinal direction is formed. Three output bump rows are arranged in parallel in the width direction of the mounting surface in the output bump region, and one input bump row is formed in the input bump region. The length A in the width direction of the output bump region was 350 μm, and the length in the width direction of the input bump region was 60 μm. The distances between the output bump area and the input bump area and the outer edge are 70 μm. The output bumps constituting the three output bump rows are arranged in a staggered pattern (see FIG. 2). The width G of the inter-bump area between the output bump area and the input bump area is about 1000 μm.

[Evaluation board]
The circuit board on which the IC chip for evaluation is mounted is a glass substrate having a thickness of 200 μm, and an Al layer is formed by so-called solid wiring on the mounting surface.

[Buffer material / anisotropic conductive film]
The IC chip is mounted by sticking the anisotropic conductive film on the mounting surface of the glass substrate, and then heat-pressing the pressing surface of the IC chip with a thermocompression bonding tool through the buffer material at a predetermined temperature, pressure, and time. went. A polyimide was used as a buffer material, and a plurality of samples having a total thickness of 100 μm were prepared while forming recesses having different depths by pasting polyimide tape.

  The same anisotropic conductive film as in the first example was used. In addition, the IC chip crimping conditions by the thermocompression bonding tool were the same as those in the first embodiment.

[Example 15]
In Example 15, the recess depth 50μm and _{D 1,} the distance _{L 1} from the output bump side of the side edge 2a of the IC chip to the recess 470Myuemu, the distance from the input bump side of the side edge 2b of the IC chip to the recess _{L 2} Is 180 μm, and the distance C ′ between the inner edge of the innermost output bump row and the end of the recess and the distance J ′ between the inner edge of the input bump row and the end of the recess are 50 μm. That is, in the cushioning material according to Example 15, the end of the concave portion is located in the inter-bump region of the IC chip, and the convex portion is overlapped to 10% of the inter-bump region width G (1000 μm) (50 μm on each side). (See FIG. 11A).

  In the connection body sample according to Example 15, the conductive particle diameter in the outer output bump row was 2.3 μm, and the conductive particle diameter in the inner output bump row was 2.2 μm.

[Example 16]
In Example 16, except that the recess depth D ₁ was used buffer material 75μm were the same conditions as in Example 15.

  In the connection body sample according to Example 16, the conductive particle diameter in the outer output bump row was 2.3 μm, and the conductive particle diameter in the inner output bump row was 2.2 μm.

[Example 17]
In Example 17, except that the recess depth D ₁ was used buffer material 25μm were the same conditions as in Example 15.

  In the connection body sample according to Example 17, the conductive particle diameter in the outer output bump row was 2.4 μm, and the conductive particle diameter in the inner output bump row was 2.2 μm.

[Example 18]
The connector sample according to Example 18, the recess recesses depth _{D 1} 50 [mu] m, the distance _{L 1} from the output bump side of the side edge 2a of the IC chip to the recess 670Myuemu, the input bump side of the side edge 2b of the IC chip distance L ₂ to is 380 .mu.m, was 250μm the 'distance J between the end portion of the inner edge and the recess of and input bumps column' distance C between the end portion of the inner edge and the recess of the innermost output bumps column . That is, in the cushioning material according to Example 18, the end of the concave portion is located in the inter-bump region of the IC chip, and the convex portion is overlapped to 50% of the inter-bump region width G (1000 μm) (250 μm on each side). (See FIG. 11A).

  In the connection body sample according to Example 18, the conductive particle diameter in the outer output bump row was 2.5 μm, and the conductive particle diameter in the inner output bump row was 2.1 μm.

[Example 19]
In Example 19, except that the recess depth D ₁ was used buffer material 25μm were the same conditions as in Example 18.

  In the connection body sample according to Example 19, the conductive particle diameter in the outer output bump row was 2.5 μm, and the conductive particle diameter in the inner output bump row was 2.2 μm.

[Comparative Example 8]
In the comparative example 8, the buffer material in which the recessed part was not formed was used. In the connection body sample according to Comparative Example 8, the conductive particle diameter in the outer output bump row was 2.9 μm, and the conductive particle diameter in the inner output bump row was 2.1 μm.

[Comparative Example 9]
In Comparative Example 9, except that the recess depth D ₁ was used buffer material 10μm were the same conditions as in Example 15.

  In the connection body sample according to Comparative Example 9, the conductive particle diameter in the outer output bump row was 2.8 μm, and the conductive particle diameter in the inner output bump row was 2.1 μm.

[Comparative Example 10]
The connector sample according to Comparative Example 10, the recess recesses depth _{D 1} 50 [mu] m, the distance _{L 1} from the output bump side of the side edge 2a of the IC chip to the recess 820Myuemu, the input bump side of the side edge 2b of the IC chip distance L ₂ to is 530 .mu.m, was 400μm the 'distance J between the end portion of the inner edge and the recess of and input bumps column' distance C between the end portion of the inner edge and the recess of the innermost output bumps column . That is, in the cushioning material according to Comparative Example 10, the end of the concave portion is positioned in the inter-bump region of the IC chip, and the convex portion is overlapped to 80% of the inter-bump region width G (1000 μm) (400 μm on each side). (See FIG. 11A).

  In the connection body sample according to Comparative Example 10, the conductive particle diameter in the outer output bump row was 2.8 μm, and the conductive particle diameter in the inner output bump row was 2.2 μm.

[Comparative Example 11]
The connector sample according to Comparative Example 11, the recess recesses depth _{D 1} 50 [mu] m, the distance _{L 1} from the output bump side of the side edge 2a of the IC chip to the recess 345Myuemu, the input bump side of the side edge 2b of the IC chip distance L ₂ until a 55 .mu.m, and -75μm the 'distance J between and inner edge and an end portion of the recess of the input bump column' innermost distance C between the inner edge and the edge of the recess of the output bump rows did. That is, in the buffer material according to Comparative Example 11, the end of the recess is located in the input / output bump region of the IC chip (see FIG. 11B), which is the length A (350 μm) in the width direction of the output bump region. ) Toward the one side edge side of 21.4%.

  In the connection body sample according to Comparative Example 11, the conductive particle diameter in the outer output bump row was 2.1 μm, and the conductive particle diameter in the inner output bump row was 2.7 μm.

As shown in Table 4, the buffer material according to Example 15-19, which has 25% or more the depth D ₁ of the total thickness T _3, 50% of the bump between regions of an IC chip end of the recess The overlapping area between the convex portion and the inter-bump region is 50% or less of the inter-bump region. Therefore, in the connection body samples according to Examples 15 to 19, the output bump region is sufficiently pressed by the thermocompression bonding tool via the cushioning material, and the inter-bump region is not excessively pressed. Therefore, the pressure of the thermocompression bonding tool concentrates on the output bump region, and warpage in the inter-bump region is suppressed, and the outer and inner output bump rows can be sufficiently pressed by the thermocompression bonding tool. Therefore, the connection body samples according to Examples 15 to 19 had good conductive properties because the conductive particle diameter after compression deformation was 2.6 μm or less even in the outer output bump row.

  On the other hand, since the recessed part is not formed in the buffer material according to Comparative Example 8, the pressing force of the thermocompression bonding tool is transmitted to the inter-bump area, and the IC chip is warped so that the inter-bump area is recessed. Therefore, in the connection body sample according to Comparative Example 8, the pressing force by the thermocompression bonding tool is insufficient in the outer output bump row, and the conductive particle diameter after compression deformation becomes 2.9 μm, which may cause conduction failure. .

Further, a cushioning material according to Comparative Example 9 shallow as 10% depth of the total thickness T ₃ of the recess, abuts the pressing surface of the IC chip is bent recess upon being pressed against the thermo-compression tool, thermocompression The tool pressing force is transmitted to the inter-bump region, and the IC chip is warped so that the inter-bump region is recessed. Therefore, in the connection body sample according to Comparative Example 9, the pressing force by the thermocompression bonding tool is insufficient in the outer output bump row, the conductive particle diameter after compression deformation becomes 2.8 μm, and there is a risk of poor conduction. .

  In the cushioning material according to Comparative Example 10, the end of the concave portion is located at the center of the inter-bump region width G, and the overlapping area of the convex portion and the inter-bump region is 80% of the inter-bump region. The pressing force of the thermocompression bonding tool was transmitted to the inter-bump region through the cushioning material, and the warp occurred so that the inter-bump region was recessed with the inner edges of the input bump row and the inner output bump row as fulcrums. Therefore, in the connection sample according to Comparative Example 10, the pressing force by the thermocompression bonding tool is insufficient in the outer output bump row, the conductive particle diameter after compression deformation is 2.8 μm, and there is a risk of poor conduction. .

  Further, in the cushioning material according to Comparative Example 11, the end of the concave portion is located 21% inside the output bump region, the overlapping area between the convex portion and the output bump region is small, and the thermocompression bonding is performed in the region overlapping the output bump region. The pressing area by the tool is biased toward one side edge, and the pressing force against the output bump array arranged on the innermost side of the output bump area is insufficient. Therefore, in the connection body sample according to Comparative Example 11, the pressing force by the thermocompression bonding tool is insufficient in the inner output bump row, and the conductive particle diameter after compression deformation becomes 2.7 μm, which may cause conduction failure. .

  As described above, it was found that, by setting the shape of the cushioning material to an appropriate range, stable anisotropic connection can be achieved in the same manner as the back surface processing of the IC chip. Since the buffer material is relatively cheaper than the IC chip, it can contribute to cost reduction. In addition, there are various bump layouts for IC chips, but there is a margin in the range of bumpy dimensions of the cushioning material that is effective, so even if the bump layout of the IC chip is changed, the cushioning material can be changed. Less is needed, and this also shows that it can contribute to cost reduction.

1 IC chip, 2 mounting surface, 2a one side edge, 2b other side edge, 3 output bump, 3A-3C output bump row, 4 output bump region, 5 input bump, 5A input bump row, 6 input bump region, 7 Bump area, 8 Press surface, 9 Recess, 10 Circuit board, 15 Buffer material, 18 Dummy bump, 19 Dummy bump area, 20 Connection body, 30 Anisotropic conductive film, 31 Release film, 32 Conductive particle, 33 Binder resin , 40 Thermocompression bonding tool, 41 Buffer material, 42 Concavity, 43 Convex

Claims (24)

An output bump area in which output bumps are arranged along one side of a pair of opposing side edges is provided on a mounting surface connected to the circuit board, and input bumps are provided along the other side of the pair of side edges. Arranged input bump areas are provided,
On the pressing surface pressed by the crimping tool on the side opposite to the mounting surface, a recess is provided that overlaps with the inter-bump region between the output bump region and the input bump region ,
One end of the output bump area or the input bump area of the concave portion is from the inner edge of the bump row arranged on the innermost side of the one bump area, and the arrangement direction of the bumps in the one bump area. An area of less than 12.5% of the length in the width direction of the one bump area toward the side edge where the one bump area in the width direction orthogonal to the width direction is provided, and the width direction of the one bump area An electronic component positioned between a region of less than 50% of the length in the width direction of the one bump region toward the side edge on which the other bump region is provided . One end of the output bump area or the input bump area of the concave portion is from the inner edge of the bump row arranged on the innermost side of the one bump area, and the arrangement direction of the bumps in the one bump area. An area having a length less than 7.5% of the length in the width direction of the one bump area toward the side edge side where the one bump area in the orthogonal width direction is provided, and the one bump area 2. The semiconductor device according to claim 1, wherein the first bump region is located between a region of less than 37.5% of the length in the width direction toward the side edge on which the other bump region in the width direction is provided. Electronic components. The electronic component according to claim 1, wherein the one bump area is an output bump area. An output bump area in which output bumps are arranged along one side of a pair of opposing side edges is provided on a mounting surface connected to the circuit board, and input bumps are provided along the other side of the pair of side edges. Arranged input bump areas are provided,
On the pressing surface pressed by the crimping tool on the side opposite to the mounting surface, a recess is provided that overlaps with the inter-bump region between the output bump region and the input bump region ,
The concave portion is an electronic component formed by providing an auxiliary member that forms a step between the bump area and the output bump area and the input bump area on the pressing surface .   The electronic component according to claim 1, wherein the concave portion is formed by cutting a pressing surface. The depth of the recess, the electronic component according to any one of claims 1 to 5, or less than 90% of substrate thickness recess is formed. In the connection body in which the electronic component is placed on the circuit board by being placed on the circuit board via an adhesive and pressed by a crimping tool,
The electronic components are
An output bump area in which output bumps are arranged along one side of a pair of opposing side edges is provided on a mounting surface connected to the circuit board, and an input bump is provided along the other side of the pair of side edges. Input bump area is arranged,
On the pressing surface pressed by the crimping tool on the side opposite to the mounting surface, a recess is provided that overlaps with the inter-bump region between the output bump region and the input bump region ,
One end of the output bump area or the input bump area of the concave portion is from the inner edge of the bump row arranged on the innermost side of the one bump area, and the arrangement direction of the bumps in the one bump area. An area of less than 12.5% of the length in the width direction of the one bump area toward the side edge where the one bump area in the width direction orthogonal to the width direction is provided, and the width direction of the one bump area The connecting body is located between a region of less than 50% of the length in the width direction of the one bump region toward the side edge on which the other bump region is provided . In the connection body in which the electronic component is placed on the circuit board by being placed on the circuit board via an adhesive and pressed by a crimping tool,
The electronic components are
An output bump area in which output bumps are arranged along one side of a pair of opposing side edges is provided on a mounting surface connected to the circuit board, and an input bump is provided along the other side of the pair of side edges. Input bump area is arranged,
On the pressing surface pressed by the crimping tool on the side opposite to the mounting surface, a recess is provided that overlaps with the inter-bump region between the output bump region and the input bump region ,
The concave portion is a connection body formed by providing an auxiliary member for forming a step between the output bump region and the input bump region on the pressing surface and a region between the bumps . The connection body according to claim 7 or 8, wherein a depth of the concave portion is 90% or less of a thickness of a substrate on which the concave portion is formed. In the method of manufacturing a connection body, in which an electronic component is arranged on a circuit board via an adhesive, and the electronic component is connected to the circuit board by applying pressure with a crimping tool.
The electronic components are
An output bump area in which output bumps are arranged along one side of a pair of opposing side edges is provided on a mounting surface connected to the circuit board, and an input bump is provided along the other side of the pair of side edges. Input bump area is arranged,
On the pressing surface pressed by the crimping tool on the side opposite to the mounting surface, a recess is provided that overlaps with the inter-bump region between the output bump region and the input bump region ,
One end of the output bump area or the input bump area of the concave portion is from the inner edge of the bump row arranged on the innermost side of the one bump area, and the arrangement direction of the bumps in the one bump area. An area of less than 12.5% of the length in the width direction of the one bump area toward the side edge where the one bump area in the width direction orthogonal to the width direction is provided, and the width direction of the one bump area A method of manufacturing a connection body positioned between a region of less than 50% of the length in the width direction of the one bump region toward the side edge on which the other bump region is provided . In the method of manufacturing a connection body, in which an electronic component is arranged on a circuit board via an adhesive, and the electronic component is connected to the circuit board by applying pressure with a crimping tool.
The electronic components are
An output bump area in which output bumps are arranged along one side of a pair of opposing side edges is provided on a mounting surface connected to the circuit board, and an input bump is provided along the other side of the pair of side edges. Input bump area is arranged,
On the pressing surface pressed by the crimping tool on the side opposite to the mounting surface, a recess is provided that overlaps with the inter-bump region between the output bump region and the input bump region ,
The method of manufacturing a connection body, wherein the concave portion is formed by providing an auxiliary member that forms a step between the output bump region and the input bump region on the pressing surface and a region between the bumps . The manufacturing method of the connection body of Claim 10 or 11 which crimps | bonds the said electronic component using the buffer material thinner than the depth of the said recessed part. The depth of the said recessed part is 90% or less of the thickness of the board | substrate with which this recessed part is formed, The manufacturing method of the connection body of any one of Claims 10-12 . In the electronic component connection method of placing the electronic component on the circuit board via an adhesive and connecting the electronic component on the circuit board by applying pressure with a crimping tool,
The electronic components are
An output bump area in which output bumps are arranged along one side of a pair of opposing side edges is provided on a mounting surface connected to the circuit board, and an input bump is provided along the other side of the pair of side edges. Input bump area is arranged,
On the pressing surface pressed by the crimping tool on the side opposite to the mounting surface, a recess is provided that overlaps with the inter-bump region between the output bump region and the input bump region ,
One end of the output bump area or the input bump area of the concave portion is from the inner edge of the bump row arranged on the innermost side of the one bump area, and the arrangement direction of the bumps in the one bump area. An area of less than 12.5% of the length in the width direction of the one bump area toward the side edge where the one bump area in the width direction orthogonal to the width direction is provided, and the width direction of the one bump area A method of connecting an electronic component that is located between a region of less than 50% of the length in the width direction of the one bump region toward the side edge side on which the other bump region is provided . In the electronic component connection method of placing the electronic component on the circuit board via an adhesive and connecting the electronic component on the circuit board by applying pressure with a crimping tool,
The electronic components are
An output bump area in which output bumps are arranged along one side of a pair of opposing side edges is provided on a mounting surface connected to the circuit board, and an input bump is provided along the other side of the pair of side edges. Input bump area is arranged,
On the pressing surface pressed by the crimping tool on the side opposite to the mounting surface, a recess is provided that overlaps with the inter-bump region between the output bump region and the input bump region ,
The method of connecting an electronic component, wherein the recess is formed by providing an auxiliary member that forms a step between the output bump area and the input bump area on the pressing surface and the inter-bump area . The method of connecting electronic parts according to claim 14 or 15 , wherein the electronic parts are pressure-bonded using a buffer material thinner than the depth of the recess. The depth of the said recessed part is 90% or less of the thickness of the board | substrate with which this recessed part is formed, The connection method of the electronic components of any one of Claims 14-16 . An output bump area in which output bumps are arranged on a mounting surface connected to the circuit board, an input bump area in which input bumps are arranged to face the output bump area, and the output bump area and the input bump area. In an electronic component having an inter-bump region provided therebetween, in a sheet-like cushioning material disposed between the pressing surface opposite to the mounting surface and the crimping tool,
A cushioning material in which a recess is formed at a position corresponding to the area between the bumps. The electronic component is provided with the output bump region in which the output bumps are arranged along one side of a pair of opposite side edges, and the input bumps are arranged along the other side of the one side edge. The cushioning material according to claim 18, wherein the input bump region is provided. The buffer material according to claim 18 or 19 , wherein the output bump region includes a plurality of bump rows in which the output bumps are arranged in parallel. The cushioning material according to any one of claims 18 to 20 , wherein the cushioning material is formed in a substantially rectangular shape, and the concave portion is formed along a longitudinal direction. The cushioning material according to any one of claims 18 to 20 , wherein a plurality of the recesses formed in a substantially rectangular shape and formed along the short direction are formed along the longitudinal direction. In the method of manufacturing a connection body, in which an electronic component is disposed on a circuit board via an adhesive, and the electronic component is connected to the circuit board by applying pressure with a crimping tool via a cushioning material,
The electronic component includes an output bump area in which output bumps are arranged on a mounting surface connected to the circuit board, an input bump area in which input bumps are arranged to face the output bump area, and the output bump area. And an inter-bump area provided between the input bump areas,
The said buffer material is a manufacturing method of the connection body by which the recessed part is formed in the position according to the said area | region between bumps. In the method of connecting electronic components, the electronic components are arranged on the circuit board via an adhesive, and the electronic components are connected to the circuit board by applying pressure with a crimping tool via a cushioning material.
The electronic component includes an output bump area in which output bumps are arranged on a mounting surface connected to the circuit board, an input bump area in which input bumps are arranged to face the output bump area, and the output bump area. And an inter-bump area provided between the input bump areas,
The said buffer material is a connection method of the electronic component in which the recessed part is formed in the position according to the said area | region between bumps.

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