JP2005116957A - Method of manufacturing semiconductor device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method of manufacturing a semiconductor device, with which the sealing method (including a step of filling underfill) of the semiconductor device that requires flip-chip bonding can be completed by a simple method without combined use of previous sealing methods, and which can sufficiently protect all faces of the chip as previous sealing methods can. <P>SOLUTION: A first method of manufacturing the semiconductor device comprises a step of forming an adhesive-film forming layer on the circuit plane of the semiconductor wafer, on the surface of which circuits are formed, a step of full-cut dicing the semiconductor wafer together with the adhesive-film forming layer to break the wafer into individual chips, a step of gluing a protecting-film forming layer on the backside and side faces of each semiconductor chip, a step of cutting the protecting-film forming layer so that the semiconductor chips are separated into individual chips, and a step of loading each chip to a prescribed position of a substrate for chip mounting, and fixing the chip to the substrate for chip mounting by adhesion while assuring electrical conduction between the chip and the substrate for chip mounting. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  In the present invention, an adhesive layer used for fixing a semiconductor chip can be easily formed on the circuit surface, and a highly uniform protective film can be easily formed on the back surface and side surface of the chip. The present invention relates to a method for manufacturing a semiconductor device capable of eliminating the adverse effects caused by such scratches even if such scratches are formed.

In recent years, IC chip mounting methods have been diversified, and there is a packaging method in which an IC chip circuit surface is disposed on the lower side. Such a packaging method is also called a face down method or flip chip bonding. In this packaging method, convex electrode elements are formed so as to protrude from the circuit surface, and the height difference thereof is 30 μm or more, and in some cases, some of them exceed 100 μm. Such convex portions formed on the surface of the semiconductor wafer are called bumps. In flip chip bonding, conduction between a chip mounting substrate such as a lead frame and the chip is ensured through the bumps.

In general, a semiconductor device is sealed with resin in order to protect the circuit surface. The same applies to the semiconductor device using the high bump chip as described above. Specifically, resin sealing is performed by the following method.
(1) The chip on which the bump is formed is placed on the chip mounting substrate, the chip and the chip mounting substrate are connected via the bump, and then resin-sealed.
(2) The high bump chip and the chip mounting substrate are connected through an anisotropic conductive paste, and then resin-sealed.

  However, in the method (1), there is a space between the chip and the chip mounting substrate by the height of the bump, and even if resin sealing is performed, the sealing resin is in this space. Insufficient penetration may cause voids. For this reason, it is necessary to fill an insulating resin (underfill) between the chip and the chip mounting substrate before resin sealing.

  In the method (2), it is necessary to apply an anisotropic conductive paste to a minute chip, which is also complicated in terms of work steps. In particular, it is difficult to apply a certain amount of anisotropic conductive paste, and the amount of paste differs from product to product, which may cause variations in product characteristics.

In order to solve such a problem, in Patent Document 1, “an adhesive thin film layer is formed on a circuit surface of a semiconductor wafer on which a circuit is formed on the surface,
The semiconductor wafer is cut and separated into individual chips for each circuit,
The individual chip is placed at a predetermined position of the chip mounting substrate through the adhesive thin film layer,
A method for manufacturing a semiconductor device, comprising: bonding and fixing the individual chip to the chip mounting substrate while ensuring conduction between the individual chip and the chip mounting substrate. Is disclosed.

  According to such a manufacturing method described in Patent Document 1, an adhesive thin film layer is formed on a wafer circuit surface, and dicing is performed to obtain a chip. Since the adhesive thin film layer is in close contact with the circuit surface of the resulting chip, voids can be prevented during resin sealing, and a product with high uniformity and reliability can be obtained.

Further, the semiconductor wafer is generally subjected to back surface grinding after the completion of the wafer process in order to make the thickness uniform and remove the oxide film. In back surface grinding, minute streak-like scratches are formed on the back surface of the chip by mechanical grinding. This minute scratch may cause cracking after packaging. For this reason, conventionally, chemical etching for removing minute scratches may be necessary after mechanical grinding. However, chemical etching necessitates equipment and operation costs as well as the cost increase.

  Therefore, even if a minute scratch is formed on the back surface of the chip by mechanical grinding, there is a demand for the development of a technique that eliminates the adverse effects caused by the scratch.

  As such a technique, the applicant of the present application has already said, "Protection comprising a release sheet, a thermosetting component and / or an energy ray curable component and a binder polymer component formed on the release surface of the release sheet. A "protective film forming sheet for chips having a film forming layer" is disclosed (see Patent Document 2). Patent Document 2 discloses a method for manufacturing a chip with a protective film, which includes a step of pasting the protective film forming sheet for a chip on the back side of a semiconductor wafer and dicing the sheet together with the wafer.

However, in any of the methods disclosed in Patent Documents, only one surface of the chip is protected, and in order to completely protect the other surface, a part of the conventionally employed sealing method must be employed separately. Further, even if both of the methods of Patent Document 1 and Patent Document 2 are adopted, the side surface of the chip is open, so that sufficient protection is not achieved. The combined use of the methods of these patent documents and the conventional sealing method does not provide the effect of the invention that enables sealing by a simple method.
JP 2001-144140 A JP 2002-280329 A

  The present invention has been made in view of the above problems, and a semiconductor device sealing method (including an underfill filling step) for performing flip chip bonding is not used in combination with a conventional sealing method. An object of the present invention is to provide a method of manufacturing a semiconductor device which can be completed only by a simple method and can sufficiently protect all surfaces of a chip as in a conventional sealing method.

A first manufacturing method of a semiconductor device according to the present invention includes:
Forming an adhesive film forming layer on a circuit surface of a semiconductor wafer having a circuit formed on the surface;
A step of full-cut dicing the semiconductor wafer and the adhesive film forming layer into chips;
A process of attaching a protective film forming layer to the back and side surfaces of each semiconductor chip;
A step of cutting the protective film forming layer so as to be divided into individual semiconductor chips, and placing the individual chips at predetermined positions on the chip mounting substrate via the adhesive film forming layer. A step of bonding and fixing the individual chip to the chip mounting substrate while ensuring conduction between the chip and the chip mounting substrate.

A second method for manufacturing a semiconductor device according to the present invention is as follows.
A step of dicing a semiconductor wafer having a circuit formed on its surface into chips,
Forming an adhesive film forming layer on the circuit surface of each semiconductor chip;
A process of attaching a protective film forming layer to the back and side surfaces of each semiconductor chip;
A step of cutting the protective film forming layer so as to be divided into individual semiconductor chips, and placing the individual chips at predetermined positions on the chip mounting substrate via the adhesive film forming layer. A step of bonding and fixing the individual chip to the chip mounting substrate while ensuring conduction between the chip and the chip mounting substrate.

A third manufacturing method of a semiconductor device according to the present invention is as follows:
A step of dicing a semiconductor wafer having a circuit formed on its surface into chips,
A process of attaching a protective film forming layer to the back and side surfaces of each semiconductor chip;
Cutting the protective film forming layer so as to be divided into individual semiconductor chips,
Forming an adhesive film forming layer on the circuit surface of each semiconductor chip;
And an individual chip is placed at a predetermined position on the chip mounting substrate via the adhesive film forming layer, and the individual chip is mounted on the chip mounting substrate while ensuring conduction between the individual chip and the chip mounting substrate. A step of bonding and fixing to the chip mounting substrate.

  According to such a method for manufacturing a semiconductor device according to the present invention, a semiconductor device for performing flip chip bonding can be sealed on the entire surface of the chip only by a simple method without using a conventional sealing method. In addition, since the same protection as that of the conventional method is performed, a semiconductor device having sufficient reliability can be manufactured.

  Hereinafter, the present invention will be described more specifically with reference to the drawings.

  Before explaining each step of the manufacturing method according to the present invention, first, a semiconductor wafer 1 which is a common element in the first to third manufacturing methods, an adhesive film forming sheet 10 for forming an adhesive film forming layer, protection The protective film forming sheet 20 for forming the film forming layer will be described.

"Semiconductor wafer 1"
Examples of the semiconductor wafer 1 include conventionally used silicon semiconductor wafers and gallium / arsenic semiconductor wafers, but are not limited thereto, and various semiconductor wafers can be used. Formation of a circuit on the wafer surface can be performed by various methods including conventionally used methods such as an etching method and a lift-off method. In the semiconductor wafer circuit forming step, a predetermined circuit is formed. Further, it is desirable that conductive protrusions (bumps) 2 used for electrical connection with the chip mounting substrate are formed on the circuit surface. The height and diameter of the bump 2 vary depending on the design of the semiconductor device, but generally the height is about 10 to 100 μm and the diameter is about 20 to 100 μm. Such bumps 2 are often formed from a metal such as gold, copper, or solder.

"Adhesive film forming sheet 10"
The adhesive film forming sheet 10 is composed of a laminate of a support film 11 and an adhesive film forming layer 12 formed on one side of the support film 11. The side of the support film 11 facing the adhesive film forming layer 12 is peelable so that the adhesive film forming layer 12 can be transferred.

  The support film 11 is preferably a film excellent in flexibility and followability so that the adhesive film forming sheet 10 can be steadily adhered to the surface on which the bumps are formed. For example, a polyethylene film, a polypropylene film, a polybutene film is preferable. , Polybutadiene film, polymethylpentene film, polyvinyl chloride film, vinyl chloride copolymer film, polyurethane film, ethylene vinyl acetate film, ionomer resin film, ethylene / (meth) acrylic acid copolymer film, ethylene / (meth) acrylic An acid ester copolymer film or the like is used. These crosslinked films are also used. Furthermore, these laminated films may be sufficient.

Furthermore, the surface tension of the support film 11 is preferably 40 mN / m or less, more preferably 37 mN / m or less, and particularly preferably 35 mN / m or less. Such a support film 11 having a low surface tension can be obtained by appropriately selecting the material, and can also be obtained by applying a silicone resin or the like to the surface of the film and performing a release treatment. .

  The film thickness of the support film 11 is usually about 5 to 300 μm, preferably about 10 to 200 μm, and particularly preferably about 20 to 150 μm.

  The adhesive film forming layer 12 is a layer having a role equivalent to that of the underfill in the conventional sealing method. The adhesive film forming layer 12 adheres the semiconductor chip 3 and the chip mounting substrate 30 and both of them through the adhesive film forming layer 12. Conduction is performed. The adhesive film forming layer 12 is made of an insulating adhesive or an anisotropic conductive adhesive.

  The insulating adhesive film forming layer 12 may be thermoplastic, thermosetting, or adhesive. The adhesiveness refers to an adhesive that exhibits pressure-sensitive adhesiveness at room temperature, cures by heating, and exhibits strong adhesiveness.

  The thermoplastic adhesive film forming layer is composed of a material mainly composed of a thermoplastic binder resin. Examples of thermoplastic binder resins include polyester resins, polyvinyl acetate resins, polyvinyl butyral resins, polyvinyl chloride resins, acrylic resins, polystyrene resins, urethane resins, polyamide resins, polyimide resins, and various hot melt adhesives. Preferably, a polyester resin or a polyimide resin is used.

  The thermosetting adhesive film forming layer is composed of a thermosetting binder resin as a main component. As the thermosetting binder resin, for example, epoxy resin, acrylic resin, polyimide resin, phenol resin, urea resin, melamine resin, resorcinol resin, urethane resin, polyester resin, benzoxazine resin, etc. are used, preferably epoxy resin, A phenol resin or a mixed system of an epoxy resin and a phenol resin is used.

  Examples of the adhesive film-forming layer that is adhesive include a mixture of a binder resin and a thermosetting resin that are adhesive at room temperature. Examples of the binder resin having pressure-sensitive adhesive properties at room temperature include acrylic resins, polyester resins, polyvinyl ethers, urethane resins, and polyamides. Examples of the thermosetting resin include the same type of resin as the above-described thermosetting binder resin, and those having a relatively low molecular weight than the binder resin can be used.

  Similarly, an anisotropic conductive adhesive film-forming layer can be used which is thermoplastic, thermosetting or adhesive. An anisotropic conductive adhesive film forming layer is usually a conductive particle dispersed in the above-mentioned insulating adhesive film forming layer, and before use, the conductive particles in the adhesive film forming layer are in contact with each other. It exists in the binder resin to the extent that it does not, and when flip-chip bonding is performed, the conductive projection as an electrode compresses the adhesive film forming layer when pressed between the chip and the chip mounting substrate, forming an adhesive film Conductive particles are in contact only in the thickness direction of the layer, are anisotropic in the planar direction, and exhibit anisotropic conductivity that conducts only in the thickness direction.

Materials used as conductive particles include powders and fibrous bodies of metal or alloys such as gold, silver, copper, nickel, and aluminum, and conductive polymer powders and fibrous bodies such as carbon black, polyaniline, and polypyrrole. Used. These materials may be used alone or in combination of two or more. Also, the shape of the powder or the like may be formed by using a conductive material alone, or may be a coating or plating on a resin such as styrene or acrylic. The size of the powder or fibrous body is preferably about 1 to 20 μm. Such conductive particles include the binder resin 10 described above.
It is used at a ratio of about 1 to 500 parts by weight with respect to 0 part by weight.

  The adhesive film forming layer 12 may contain a filler. Examples of the filler include silica such as crystalline silica and synthetic silica, and inorganic filler such as alumina and glass balloon. By adding an inorganic filler to the adhesive film forming layer 12, the thermal expansion coefficient of the cured layer can be brought close to the thermal expansion coefficient of the chip, thereby reducing the stress applied to the chip. Become.

  Further, additives having various functionalities such as coupling agents, pigments, dyes, crosslinking agents, antistatic agents, and flame retardants are blended in the adhesive film forming layer 12 in accordance with the performance required by the semiconductor device. Can do.

  The adhesive film forming layer 12 is formed by coating the composition comprising the above components on the release surface of the support film 11 directly or by transfer according to a generally known method such as a roll knife coater, gravure coater, die coater, reverse coater, and the like. And forming the adhesive film forming layer 12. In addition, said composition can be apply | coated after making it melt | dissolve or disperse | distribute to a solvent as needed.

The film thickness of the adhesive film forming layer 12 is preferably about 1 to 1000 μm, although it depends on the height of the conductive protrusion 2 provided on the semiconductor chip 3 side or the chip mounting substrate 30 side. Preferably it is about 5-200 micrometers, Most preferably, it is about 10-100 micrometers.

  Another release film (not shown) may be provided on the surface of the adhesive film forming layer 12 that is not on the support film side. The adhesive film forming layer 12 is laminated with the support film 11 and another release film, so that the adhesive film forming layer 12 is not deformed by tension or pressure during storage or pasting work, and dust or the like adheres to the surface. Disappears.

  As the other release film, one obtained by subjecting one side of a rigid film such as a polyethylene terephthalate film, a polybutylene terephthalate film, a polyethylene naphthalate film, a polycarbonate film, a polystyrene film, or a polyimide film to a release treatment can be used. Moreover, you may use the film excellent in the flexibility and followable | trackability employ | adopted as the support film 11. FIG.

  The adhesive film forming sheet 10 is attached to the semiconductor wafer 1 or the semiconductor chip 3 by an attaching device. The pressure at the time of sticking is appropriately set according to the sticking method (rubber roller type, vacuum contact type) of the sticking device, but if the pressurization condition is too weak, the adhesive film forming sheet 10 does not stick to the wafer or chip. If it is too strong, the wafer and chip may be damaged.

  Further, when the adhesive film forming sheet 10 is affixed to the semiconductor chip 3, a cut having the same shape as the chip may be provided in the adhesive film forming layer 12 in advance.

  The application temperature depends on the properties of the adhesive film forming sheet to be used. Usually, a temperature not lower than the plasticization temperature of the binder resin and not higher than 180 ° C. is preferred. In addition, when an adhesive is used, it can be stuck at room temperature. If the sticking temperature is too high, the wafer may be warped after grinding. If the bump 2 provided on the circuit surface of the wafer has a large unevenness on the circuit surface of the wafer, the wafer 2 is applied under conditions higher than the standard pressure condition or at a higher application temperature. It is preferable to adhere to the circuit surface.

"Protective film forming sheet 20"
The protective film forming sheet 20 is composed of a laminate of a support film 21 and a protective film forming layer 22 formed on one side of the support film 21.

  The support film 21 used for the protective film-forming layer sheet 20 is preferably a film having excellent flexibility and followability because the protective film-forming layer 22 is securely adhered to the side surface as well as the back surface of the chip. A film of the same kind and thickness as the support film 11 of the forming sheet 10 can be used.

  The protective film forming layer 22 is transferred to the back surface and side surface of the semiconductor chip 3 and serves as a mold resin in the conventional sealing method. The protective film forming layer 22 preferably has a composition in which a thermosetting component and / or an energy ray curable component is blended with a binder resin. The protective film forming layer 22 is configured to be insulating.

  As the binder resin of the protective film forming layer 22, any of a thermoplastic binder resin, a thermosetting binder resin, and a binder resin that is adhesive at room temperature can be used. As a thermosetting component, the thermosetting binder resin or thermosetting resin used for the adhesive film formation layer 12 mentioned above can be used.

  The energy ray curable component is composed of a compound that is polymerized and cured when irradiated with energy rays such as ultraviolet rays and electron beams. Specifically, low-molecular polyvalent (meth) acrylates such as trimethylolpropane triacrylate, pentaerythritol tetraacrylate, dipentaerythritol hexaacrylate, oligomers such as oligoester acrylate, urethane acrylate, and epoxy-modified acrylate are used. Can do.

  When an energy ray curable component is used, the polymerization curing time and the amount of light irradiation can be reduced by mixing a photopolymerization initiator.

  The protective film forming layer 22 may also contain functional additives such as fillers, coupling agents, pigments, dyes, cross-linking agents, antistatic agents, and flame retardants, like the adhesive film forming layer 12.

  The protective film forming sheet 20 is a generally known method such as a roll knife coater, a gravure coater, a die coater, a reverse coater, or the like, on the release surface of a support sheet 21 or other release film (not shown). Thus, the protective film forming layer 22 can be obtained by coating directly or by transfer and drying. In addition, said composition can be apply | coated after making it melt | dissolve or disperse | distribute to a solvent as needed.

  The thickness of the protective film forming layer 22 thus formed is usually 3 to 100 μm, preferably 10 to 60 μm.

Further, the protective film forming layer 22 may have two or more constituent layers. In this case, it is preferable to provide a layer having excellent adhesion to the chip on the layer that is in close contact with the chip (that is, the layer that is in contact with another release film not shown). Specifically, excellent adhesion to the chip can be obtained by increasing the blending amount of the binder resin component. In this case, it is preferable to provide a layer that forms a relatively hard cured film as the outermost layer (that is, the layer in contact with the support sheet 21). Specifically, a hard cured film can be obtained by increasing the blending ratio of the filler component, the thermosetting component and / or the energy ray curable component. The uppermost layer may be provided with irregularities in order to provide printability. Specifically, the printability is controlled by adding a filler or using a support film having an embossed release surface as the support sheet 21 and transferring the embossed pattern of the support sheet 21 to the uppermost layer. be able to.

"First manufacturing method"
A first manufacturing method of a semiconductor device according to the present invention includes:
A step of forming the adhesive film forming layer 12 on the circuit surface of the semiconductor wafer 1 described above (hereinafter referred to as “A1 step”);
A step of cutting the semiconductor wafer 1 and the adhesive film forming layer 12 into chips by full-cut dicing (hereinafter referred to as “A2 step”);
A step of attaching a protective film forming layer 22 to the back and side surfaces of each semiconductor chip 3 (hereinafter referred to as “A3 step”);
A step of cutting the protective film forming layer 22 so as to be divided into individual semiconductor chips 3 (hereinafter referred to as “A4 step”), and the individual chip 3 through the adhesive film forming layer 12; 30 and a step of adhering and fixing the individual chip 3 to the chip mounting substrate 30 (hereinafter referred to as “step A5”) while ensuring conduction between the individual chip 3 and the chip mounting substrate 30. ")including.

Hereinafter, details of each process will be described.
(Step A1)
As described above, the formation of the adhesive film forming layer 12 on the circuit surface of the semiconductor wafer 1 (A1 step) is performed by attaching the adhesive film forming sheet 10 using a normal attaching device. The pressure at the time of sticking is appropriately set by the sticking method (rubber roller type, vacuum contact type) of the sticking device. However, if the pressurization condition is too weak, the adhesive film forming sheet 10 may not stick to the wafer. If it is too strong, the wafer may be damaged.

Thereafter, dicing of the semiconductor wafer (step A2) is performed, but the backside grinding of the semiconductor wafer 1 may be performed as necessary prior to dicing. The back surface grinding step of the semiconductor wafer 1 is a step of removing the oxide film formed on the back surface of the wafer during circuit formation and grinding the wafer to a predetermined thickness. The back surface grinding can be performed by a conventionally known method such as a grinding apparatus. In the present invention, by sticking the adhesive film forming sheet 10 to the wafer circuit surface before the back surface grinding, a function as a protective sheet for wafer back surface grinding can be expressed.
(Step A2)
Next, as shown in FIG. 1 or FIG. 2, the wafer is diced (step A2). The dicing of the wafer is performed using a normal dicing apparatus. In the embodiment shown in FIG. 1, dicing is performed by attaching a dicing tape 4 to the back surface of the wafer and fixing the dicing tape 4 to the circular frame 5 via the dicing tape 4. In the embodiment shown in FIG. 2, dicing tape 4 is attached to the back surface of the support film 11, and the dicing is performed by fixing the dicing tape 4 to the circular frame 5. When dicing, the adhesive film forming layer 12 is also cut together with the wafer. Moreover, when the support film 11 is laminated | stacked on the adhesive film formation layer 12, the support film 11 is also cut | disconnected simultaneously. As the dicing tape 4, various adhesive tapes conventionally used for this type of application are used without any particular limitation.

1 and 2 show a mode in which the support film 11 is laminated on the adhesive film forming layer 12, the support film 11 places the individual chips 3 diced on the chip mounting substrate. It may be peeled off from the adhesive film forming layer 12 before the step (A5 step). That is, the support film 11 may be peeled off from the adhesive film forming layer 12 at any stage after the A1 process and before the A5 process. A method of peeling the support film 11 from the adhesive film forming layer 12 is performed by attaching a wide adhesive sheet to the entire surface of the support film 11 and then peeling it off at an acute angle. The support film 11 is preferably peeled after dicing, but may be before dicing. Hereinafter, the drawings show an embodiment in which the support film 11 is peeled after dicing.
(Step A3)
Next, the protective film forming layer 22 is formed by sticking the protective film forming sheet 20 to the back and side surfaces of each semiconductor chip 3 (step A3).

When the dicing process is performed in the mode of FIG. 1, the A3 process can be performed by any of the following three methods.
(A3a method)
When the dicing process is performed in the form of FIG. 1, since the back surface of the chip is not exposed, the chip 3 is first transferred to another adhesive tape 6 (FIG. 3). As the other adhesive tape 6, an adherend can be peeled again, and a tape having expandability is used. As the other adhesive tape 6, since the above-mentioned dicing tape generally has removability and excellent expandability, it can be appropriately selected from commercially available ones.

  Next, the adhesive tape 6 is expanded to widen the interval between adjacent chips (FIG. 4). The expanding step can be performed by a known method. The interval between the chips is sufficient as long as the protective film-forming sheet 20 can be attached, and is generally 0.1 to 3 mm, preferably about 0.2 to 2 mm.

  Thereafter, as shown in FIG. 5, the protective film forming sheet 20 is stuck so as to be in close contact with the back surface and the side surface of each semiconductor chip 3. At this time, if necessary, the protective film forming sheet 20 may be brought into close contact with each chip by applying a pressure that does not destroy the semiconductor chip.

As described above, the protective film forming sheet 20 is adhered to the back surface and the side surface of each semiconductor chip 2.
(A3b method)
In this method, the chip 3 is picked up after the dicing step (step A2). In the drawings, the support film 11 is peeled off after dicing.

  The picked-up semiconductor chips 3 are attached to the protective film forming sheet 20 so that the respective chips 3 are spaced apart from each other at a predetermined interval so that the back surface side of each chip 3 faces. The protective film forming sheet 20 is adhered to the back surface and the side surface of each semiconductor chip 3 by bringing the 20 spaced portions into close contact with the side surface of each chip.

  For example, as shown in FIG. 6, the A3b method can be performed using a jig 40 having cavities 41 slightly larger than the chip 3 at predetermined intervals. The size of the cavity 41 is appropriately determined in consideration of the thickness of the chip 3 and the protective film forming sheet 20.

  The protective film forming sheet 20 is placed on the jig 40 so that the protective film forming layer 22 is positioned above.

  Next, when the chip 3 is placed so that the back surface of the chip faces the protective film forming layer 22 and pressure is applied so as to push the chip 3 into the cavity 41, the back surface and the side surface of the chip 3 are protected by the protective film forming layer. Adhere to 40.

  Further, the chip 3 may be guided into the cavity by vacuum suction from the inside of the cavity 41, and the back surface and the side surface of the chip 3 may be brought into close contact with the protective film forming sheet 20.

Furthermore, a shrinkable film may be used as the support film 21 of the protective film forming sheet 20. When the shrinkable film is shrunk, the protective film forming sheet 20 is shrunk so as to wrap the chip 3, and the back surface and side surfaces of the chip 3 are in close contact with the protective film forming sheet 20. Here, various resin films uniaxially or biaxially stretched are used as the shrinkable film. (A3c method)
In this method, the chip 3 is picked up after the dicing step (step A2). In the drawings, the support film 11 is peeled off after dicing.

  The picked-up semiconductor chips 3 are placed on the table 50 so that the back surfaces of the chips 3 are exposed in an arrangement in which the chips 3 are spaced apart from each other at a predetermined interval. A protective film forming sheet 20 is adhered to the substrate (FIG. 7).

  As the table 50, a table having a function of holding the chip 3 is used, and a vacuum suction type suction table is preferably used. The front surface (circuit surface) side of the chip is placed and held on the table 50 so that the back surface side of the chip is exposed. Thereafter, as shown in FIG. 7, the protective film forming layer 22 side of the protective film forming sheet 20 is attached to the back surface of the chip. Thereafter, the back surface and side surfaces of the chip 3 are brought into close contact with the protective film forming sheet 20 by means such as the above-described pressure bonding, vacuum suction, or using a shrinkable support film.

  In addition, when the dicing process is performed in the form of FIG. 2, since the back side of the chip is already exposed, the chip is attached to the dicing tape 4 without transferring the chip to another adhesive tape 6. In such a state, the dicing tape 4 is expanded to widen the interval between adjacent chips, and then the protective film forming sheet 20 may be attached in the same manner as in the A3a method. In this case, the above A3b method and A3c method can also be employed.

The protective film forming sheet 20 is attached to the back surface and the side surface of the chip 3 by the A3a method, A3b method, and A3c method as described above. In this state, the chips 3 are connected to each other via the protective film forming sheet 20.
(Step A4)
Therefore, in this invention, after peeling off the support film 21 as needed, this sheet | seat 20 for protective film formation is cut | disconnected, and it cut-divides for every chip | tip (A4 process). This cutting step can be performed by a known method in the same manner as the dicing step described above.

  Next, the protective film forming layer 22 is cured by heating and / or energy ray irradiation (curing step), and a cured film (protective film) is formed on the back surface and side surfaces of the semiconductor chip. The conditions for heating and / or energy beam irradiation are appropriately set depending on the composition of the protective film forming layer 22. When a thermosetting component and an energy beam curable component are used in combination as the curable component, the curing step of the protective film forming layer may be performed simultaneously with heating and energy beam irradiation or sequentially. In particular, it is preferable to provide a protective film forming layer on the chip and then irradiate energy rays to semi-cure the protective film forming layer, and then completely cure the protective film forming layer by heating to form a protective film.

  In addition, in the 1st manufacturing method of this invention, peeling of the support film 21 mentioned above, cutting | disconnection of the sheet | seat 20 for protective film formation, and implementation of the hardening are not limited to this order. For example, after the peeling process, the curing and cutting processes may be performed, and the order of cutting, curing, peeling, cutting, peeling, curing order, curing, peeling, cutting order, or curing, cutting, peeling order. You may go on. Furthermore, you may perform hardening of the protective film formation layer 22 in A5 process mentioned later.

Through such steps A1 to A4, the chip 3 having the adhesive film forming layer 12 on the circuit surface and the protective film forming layer 22 or a cured film thereof on the back surface and the side surface is obtained.
(Step A5)
Next, in the present invention, the chip is mounted on the chip mounting substrate 30 by flip chip bonding.

  Specifically, the individual chip 3 is placed at a predetermined position on the chip mounting substrate 30 via the adhesive film forming layer 12, and electrical connection between the individual chip 3 and the chip mounting substrate 30 is established. The individual chips 3 are bonded and fixed to the chip mounting substrate 30 while securing.

When the adhesive film forming layer 12 is made of an insulating adhesive, a chip having a conductive protrusion 2 on the circuit is used as the chip 3, or a chip mounting having a conductive protrusion 2 'is used. A substrate 30 is used. Of course, you may use these together. FIG. 8 shows an example in which a chip 3 having a conductive protrusion 2 and a chip mounting substrate 30 having a conductive protrusion 2 ′ are used in combination.

In this case, the chip 3 having the insulating adhesive film forming layer 12 transferred to the circuit surface is mounted on the chip mounting substrate 30 having the bumps 2 and 2 ′ via the insulating adhesive film forming layer 12. Put.
At this time, since the chip 3 and the chip mounting substrate 30 are not electrically connected, the insulating adhesive 12 is fluidized to connect the chip 3 and the chip mounting substrate 30 via the bumps 2 and 2 ′. After securing the conduction, the chip 3 is fixed.

When the insulating adhesive film forming layer 12 is made of a thermosetting insulating adhesive or an adhesive adhesive adhesive, the chip 3 is mounted on the chip via the insulating adhesive film forming layer 12. After mounting on the substrate 30, the insulating adhesive is heated and fluidized so as not to be cured, and conduction between the chip 3 and the chip mounting substrate 30 is achieved via the bumps 2, 2 ′. After securing, the chip is fixed by heating above the curing temperature of the insulating adhesive. It is preferable that both the adhesive film forming layer 12 and the protective film forming layer 22 are not thermosetting. However, when both of the adhesive film forming layer 12 and the protective film forming layer 22 are selected to be thermosetting or adhesive, the curing temperature of the protective film forming layer 22 that is cured first is set to a low temperature. Then, by setting the curing temperature of the adhesive film forming layer 12 to be cured next to a high temperature, it is possible to prevent the adhesive film forming layer 12 from being cured when the protective film forming layer 12 is cured.

Further, when the insulating adhesive film forming layer 12 is made of a thermoplastic insulating adhesive, after the chip 3 is placed on the chip mounting substrate 30 via the thermoplastic insulating adhesive, After the thermoplastic insulating adhesive is heated and fluidized to ensure electrical conduction between the chip 3 and the chip mounting substrate 30 via the bumps 2 and 2 ′, the thermoplastic insulating adhesive The chip is fixed by cooling below the plasticizing temperature.

In the case where the adhesive film forming sheet is made of an anisotropic conductive adhesive, the chip 3 is placed on the chip mounting substrate 30 and then subjected to pressure bonding, thereby moving the anisotropic conductive adhesive film forming layer 12 in the thickness direction. Thus, the electrical connection between the chip 2 and the chip mounting substrate 30 is ensured. In this case, the chip 3 and the chip mounting substrate 30 may have both the bumps 2 and 2 ′.
Moreover, you may have only either one. FIG. 9 shows an example in which a chip 3 having bumps 2 is used.

  When the anisotropic conductive adhesive film forming layer 12 is made of a thermosetting anisotropic conductive adhesive or an adhesive-type anisotropic conductive adhesive, the chip 3 is attached to the anisotropic conductive adhesive film. After mounting on the chip mounting substrate 30 via the formation layer 12, the chip 3 is fixed by heating to a temperature equal to or higher than the curing temperature of the anisotropic conductive adhesive. Further, when the anisotropic conductive adhesive film forming layer 12 is made of a thermoplastic anisotropic conductive adhesive, the chip mounting substrate 30 is inserted into the chip 3 via the thermoplastic anisotropic conductive adhesive film forming layer 12. After mounting on the chip, thermocompression bonding is performed to fix the chip.

Bonding and fixing of the chip 3 and the chip mounting substrate 30 can be performed by a flip chip bonder or the like. The flip chip bonder is preferably one that can accurately set the heating condition and the pressing condition. According to such a method for manufacturing a semiconductor device according to the present invention, the chip 3 and the chip mounting substrate 30 can be fixed in close contact with each other without generating a space. Further, since the cured film of the protective film forming layer 22 is also formed on the back surface and the side surface of the chip 3, it is not necessary to perform resin sealing separately, and a highly reliable semiconductor device without voids can be obtained. .
"Second manufacturing method"
A second method for manufacturing a semiconductor device according to the present invention is as follows.
A step of dicing a semiconductor wafer having a circuit formed on its surface into chips (hereinafter referred to as “B1 step”),
A step of forming an adhesive film forming layer 12 on the circuit surface of each semiconductor chip 3 (hereinafter referred to as “B2 step”);
A step of attaching a protective film forming layer 22 to the back and side surfaces of each semiconductor chip 3 (hereinafter referred to as “B3 step”);
A step of cutting the protective film forming layer 22 so as to be divided into individual semiconductor chips (hereinafter referred to as “B4 step”), and the individual chip 3 through the adhesive film forming layer 12; A step of adhering and fixing the individual chip 3 to the chip mounting substrate 30 while ensuring electrical continuity between the individual chip 3 and the chip mounting substrate 30 (hereinafter referred to as “step B5”). )including.
(Step B1)
The dicing of the wafer is performed using a normal dicing apparatus. That is, as described in the description of the A2 step, the dicing tape 4 is attached to the back surface of the wafer, and the dicing is performed by fixing the dicing tape 4 to the circular frame 5 via the dicing tape 4. As the dicing tape 4, various adhesive tapes conventionally used for this type of application are used without any particular limitation.
(Step B2)
By the B1 process, the chips are aligned and fixed on the dicing tape 4 while maintaining the wafer shape. Next, an adhesive film forming layer 12 is formed on the circuit surface of each semiconductor chip 3. The adhesive film forming layer 12 can be formed by the following method.
(B2a method)
The adhesive film forming sheet 10 is formed so as to cover the entire exposed surface of the chip (FIG. 10), and then the adhesive film forming layer 12 is cut into each chip shape (FIG. 11). The adhesive film forming layer 12 may be cut using a cutter or a dicing blade, or the dicing tape 4 may be expanded to cut the adhesive film forming layer 12. In this case, the adhesive film forming layer 12 stuck on the chip is not stretched, and only the adhesive film forming layer 12 existing in the gap between the chips is stretched. When the gap between the chips is stretched, the adhesive film forming layer 12 is cut at this portion.

Moreover, when performing postscript B3 process by said A3a method, the aspect by which the adhesive film formation layer 12 is cut | disconnected simultaneously with the extending | stretching of the adhesive tape 6 may be sufficient.
(B2b method)
Further, as shown in FIG. 12, the adhesive film forming layer 12 on the support film 11 is provided with a cut having the same shape as the chip, and the cut piece of the adhesive film forming layer 12 is bonded to each chip 3. Good.
(Step B3), (Step B4), (Step B5)
These steps are performed in the same manner as the above-mentioned (A3 step), (A4 step), and (A5 step).

A third manufacturing method of a semiconductor device according to the present invention is as follows:
A process of dicing the semiconductor wafer 1 having a circuit formed on its surface into chips (hereinafter referred to as “C1 process”),
A step of attaching a protective film forming layer 22 to the back and side surfaces of each semiconductor chip 3 (hereinafter referred to as “C2
Process "),
A step of cutting the protective film forming layer 22 so as to be divided into individual semiconductor chips (hereinafter referred to as “C3 step”),
A step of forming an adhesive film forming layer 12 on the circuit surface of each semiconductor chip 3 (hereinafter referred to as “C4 step”);
The individual chip 3 is placed at a predetermined position on the chip mounting substrate 30 via the adhesive film forming layer 12, and the electrical connection between the individual chip 3 and the chip mounting substrate 30 is ensured. This includes a step of bonding and fixing individual chips 3 to the chip mounting substrate 30 (hereinafter referred to as “C5 step”).

  Step C1 is the same as step B1.

  Steps C2 and C3 are performed in the same manner as steps A3 and A4, except that the adhesive film forming layer 12 is not formed on the circuit surface side.

  As a result, a chip having the protective film forming layer 22 on the back surface and side surfaces is obtained. In step C4, the adhesive film forming layer 12 is formed on the circuit surface side of the individual chip. In this case, it is preferable to cut the adhesive film forming layer 12 in the same shape as the circuit surface in advance and attach this to the circuit surface of the chip.

  Thereafter, a semiconductor device is obtained in the same manner as in step A5.

  According to the method for manufacturing a semiconductor device according to the present invention, a semiconductor device for performing flip chip bonding can be sealed on the entire surface of the chip by a simple method without using a conventional sealing method. In addition, since the same protection as the conventional method is applied, a semiconductor device having sufficient reliability can be manufactured.

1 process of the 1st manufacturing method of the semiconductor chip based on this invention is shown. 1 process of the 1st manufacturing method of the semiconductor chip based on this invention is shown. 1 process of the 1st manufacturing method of the semiconductor chip based on this invention is shown. 1 process of the 1st manufacturing method of the semiconductor chip based on this invention is shown. 1 process of the 1st manufacturing method of the semiconductor chip based on this invention is shown. 1 process of the 1st manufacturing method of the semiconductor chip based on this invention is shown. 1 process of the 1st manufacturing method of the semiconductor chip based on this invention is shown. 1 process of the 1st manufacturing method of the semiconductor chip based on this invention is shown. 1 process of the 1st manufacturing method of the semiconductor chip based on this invention is shown. 1 process of the 2nd manufacturing method of the semiconductor chip based on this invention is shown. 1 process of the 2nd manufacturing method of the semiconductor chip based on this invention is shown. 1 process of the 2nd manufacturing method of the semiconductor chip based on this invention is shown.

Explanation of symbols

1 ... Semiconductor wafer 2, 2 '... Bump (conductive protrusion)
DESCRIPTION OF SYMBOLS 3 ... Semiconductor chip 4 ... Dicing tape 5 ... Ring frame 6 ... Adhesive tape 10 ... Adhesive film forming sheet 11 ... Support film 12 ... Adhesive film forming layer 13 ... Release sheet 20 ... Protective film forming sheet 21 ... Support film 22 ... Protective film forming layer 30 ... Chip mounting substrate 40 ... Jig 41 ... Cavity 50 ... Suction table

Claims (3)

Forming an adhesive film forming layer on a circuit surface of a semiconductor wafer having a circuit formed on the surface;
A step of full-cut dicing the semiconductor wafer and the adhesive film forming layer into chips;
A process of attaching a protective film forming layer to the back and side surfaces of each semiconductor chip;
A step of cutting the protective film forming layer so as to be divided into individual semiconductor chips, and placing the individual chips at predetermined positions on the chip mounting substrate via the adhesive film forming layer. A method for manufacturing a semiconductor device, comprising a step of bonding and fixing the individual chip to the chip mounting substrate while ensuring conduction between the chip and the chip mounting substrate. A step of dicing a semiconductor wafer having a circuit formed on its surface into chips,
Forming an adhesive film forming layer on the circuit surface of each semiconductor chip;
A process of attaching a protective film forming layer to the back and side surfaces of each semiconductor chip;
A step of cutting the protective film forming layer so as to be divided into individual semiconductor chips, and placing the individual chips at predetermined positions on the chip mounting substrate via the adhesive film forming layer. A method for manufacturing a semiconductor device, comprising a step of bonding and fixing the individual chip to the chip mounting substrate while ensuring conduction between the chip and the chip mounting substrate. A step of dicing a semiconductor wafer having a circuit formed on its surface into chips,
A process of attaching a protective film forming layer to the back and side surfaces of each semiconductor chip;
Cutting the protective film forming layer so as to be divided into individual semiconductor chips,
Forming an adhesive film forming layer on the circuit surface of each semiconductor chip;
And an individual chip is placed at a predetermined position on the chip mounting substrate via the adhesive film forming layer, and the individual chip is mounted on the chip mounting substrate while ensuring conduction between the individual chip and the chip mounting substrate. A method for manufacturing a semiconductor device, comprising a step of bonding and fixing to a chip mounting substrate.