KR100716809B1 - A PCB using the ACF and manufacturing method thereof - Google Patents

Abstract

The present invention implements electrical connection between layers without forming via holes by heating and pressing a via hole corresponding portion in a core layer formed of an anisotropic conductive film, thereby greatly improving the density of circuits per unit area, as well as reducing signal delay caused by internal via holes. The present invention relates to a printed circuit board using an anisotropic conductive film which greatly improves electrical performance of a printed circuit board, and a method of manufacturing the same.

Anisotropic conductive film, printed circuit board, copper foil layer, plating layer, resist pattern

Description

A printed circuit board using an anisotropic conductive film and a method for manufacturing the same {A PCB using the ACF and manufacturing method}

1A to 1L are process diagrams illustrating a method of manufacturing a multilayer printed circuit board formed by a conventional build-up method.

2 is a perspective view of an inner via hole in a multilayer printed circuit board formed by a conventional build-up method.

3 is a cross-sectional view of a printed circuit board using an anisotropic conductive film according to the present invention.

4A to 4H are process charts illustrating a method of manufacturing a two-layer printed circuit board using an anisotropic conductive film according to a first embodiment of the present invention.

5A to 5J are process charts illustrating a method of manufacturing a multilayer printed circuit board using an anisotropic conductive film according to a second embodiment of the present invention.

6A to 6J are process diagrams illustrating a method of manufacturing a multilayer printed circuit board using an anisotropic conductive film according to a third embodiment of the present invention.

Explanation of symbols on the main parts of the drawings

110, 210, 260, 310: Anisotropic conductive film 120, 220, 270, 320: Copper foil layer

130: etching resist pattern 140, 230, 330: inner circuit pattern

150, 390: resist pattern 160, 340: connecting line pattern

170, 300, and 410: solder resist pattern 240: first connection line pattern

250, 350: base substrate 280, 400: outer circuit pattern

290: second connection line pattern 360: insulating layer

370: blind via hole 380: seed layer

The present invention relates to a printed circuit board and a method of manufacturing the same.

More specifically, the present invention relates to a printed circuit board using an anisotropic conductive film capable of electrically connecting layers without forming via holes by heating and pressing a corresponding portion of the via hole in the anisotropic conductive film, and a method of manufacturing the same.

As electronic products become smaller and thinner, thinner, denser, more compact, and smaller in size, more and more, multilayer printed circuit boards are also undergoing fine patterns, miniaturization, and packaging. Accordingly, in order to increase the micropattern formation, reliability, and design density of multilayer printed circuit boards, there is a tendency to change the structure of the multilayer structure of the circuit together with the change of raw materials, and the parts are also SMT (Dual In-Line Package) type. As the surface mount technology type is changed, the mounting density is also increasing. In addition to the portableization of electronic devices, the design of printed circuit boards is complicated and requires high-level technology due to high functionalization, the Internet, video, and transmission and reception of high-capacity data.

The printed circuit board includes a single-sided PCB in which wiring is formed only on one side of the insulated substrate, a double-sided PCB in which wiring is formed on both sides, and an MLB (Multi Layered Board) that is wired in multiple layers. In the past, single-sided PCBs were used because of simple components and simple circuit patterns. However, in recent years, due to increased complexity of circuits and increased demand for high-density and miniaturized circuits, it is common to use double-sided PCBs or MLBs.

The MLB is an additional wiring layer formed to enlarge the wiring area. Specifically, the MLB is divided into an inner layer and an outer layer, and a four-layer MLB (two inner layers, two outer layers) having a thin core (T / C) as a material of the inner layer, and a prepreg bonded to the outer layer and the inner layer. Floor). That is, the multilayer printed circuit board has at least four layers. As the complexity of the circuit increases, it may be composed of six, eight, and ten or more layers.

Hereinafter, a manufacturing process of a multilayer printed circuit board formed by a conventional build-up method will be described in detail with reference to FIG. 1.

Here, the build-up method refers to a manufacturing method of forming an inner layer where a circuit pattern is formed, and additionally stacking outer layers one by one.

First, as shown in FIG. 1A, a copper clad laminate (CCL; Copper Clad Laminate) 11 having a thin copper foil 12 formed on both surfaces thereof is provided through an insulating layer 13.

Here, the copper clad laminate 11 is a thin plate coated with a thin copper layer on an insulating layer, which is generally a printed circuit board, and is made of glass / epoxy copper clad laminate, heat-resistant resin copper clad laminate, and paper / phenol copper clad laminate according to its use. There are many kinds of high frequency copper clad laminates, flexible copper clad laminates (polyimide films) and composite copper clad laminates, but glass / epoxy copper clad laminates are mainly used for double-sided PCBs and multilayer PCBs.

Thereafter, as illustrated in FIG. 1B, an inner via hole 14 is formed in the copper clad laminate 11 by drilling.

Here, the inner via hole 14 electrically connects the upper and lower portions of the copper-clad laminate 11.

As described above, after forming the inner via hole 14 in the copper-clad laminate 11, as shown in Figure 1c, the electroplated copper plating and electrolytic copper plating for the copper foil layer and the via hole to perform a copper plating layer (15) ).

The copper plating layer 15 formed in the via hole 14 allows interlayer electricity to flow, and the copper plating layer 15 formed in the copper foil layer forms an internal circuit pattern together with the copper foil layer.

Here, electroless copper plating is performed first and then electrolytic copper plating is performed because electrolytic copper plating that requires electricity cannot be performed on the insulating layer. That is, in order to form the electroconductive film required for electrolytic copper plating, electroless copper plating is thinly performed as the pretreatment. Since electroless copper plating has a disadvantage in that it is difficult to process and economical, it is preferable to form the conductive portion of the circuit pattern by electrolytic copper plating.

After the electroless and electrolytic copper plating is performed as described above, as shown in FIG. 1D, the electroless and electrolytic copper plating layer 15 formed on the inner wall of the via hole 14 is embedded in the inner region of the via hole to protect the electroless and electrolytic copper plating layer 15. The ink 16 is filled.

Here, the embedding ink 16 is generally used as an insulating ink paste, but a conductive paste may also be used depending on the purpose of the printed circuit board. The conductive paste is obtained by mixing a metal such as Cu, Ag, Au, Sn, Pb as a main component alone or in an alloy form with an organic adhesive.

In this case, the via hole may be filled by performing peel plating instead of filling the filling ink.

Thereafter, as shown in FIG. 1E, an etching resist pattern 17 for forming a circuit pattern of the inner layer circuit is formed.

In order to form the etching resist pattern 17, the circuit pattern printed on the mask must be transferred onto the substrate. There are various methods for transferring, but the most commonly used method is a method of transferring a circuit pattern printed on a mask by ultraviolet light to a dry film using a photosensitive dry film. Recently, LPR (Liquid Photo Resist) is used instead of dry film.

The dry film or LPR to which the circuit pattern is transferred serves as the etching resist 17, and when the substrate is immersed in the etching solution, as shown in FIG. 1F, the copper foil layer in the region where the etching resist pattern 17 is not formed. (15) is removed to form an inner layer circuit pattern.

After forming the circuit pattern as described above, as shown in Figure 1g, by using an insulating layer 18 or Resin Coated Copper (RCC) on both sides of the substrate.

In this invention, the method to form using an insulating layer is demonstrated.

Thereafter, as shown in FIG. 1H, the blind via hole 19 serving as a folding connection between the inner layer and the outer layer is processed.

In this case, the blind via hole 19 may use mechanical drilling, but it is preferable to use YAG (Yttrium Aluminum Garnet) laser or CO2 laser because it requires more precise processing than when processing the through hole. The YAG laser is a laser capable of processing both a copper foil layer and an insulating layer, and the CO2 laser is a laser capable of processing only an insulating layer.

After the blind via hole 19 is processed as described above, the seed layer 20 is formed by electroless plating as shown in FIG. 1I.

Here, in order to form a high-density fine circuit pattern, the thickness of the electroless plating layer constituting the seed layer 20 is low.

Thereafter, as shown in FIG. 1J, the resist pattern 21 is formed on the seed layer 20 using a photolithography process.

After the resist pattern 21 is formed as described above, copper plating is performed as shown in FIG. 1K, the resist pattern 21 is peeled off, and the open seed layer 20 is removed to remove the outer circuit pattern 22. ).

Thereafter, as shown in FIG. 1L, the solder resist is coated and dried, the mask is closely adhered, the exposure and development are performed, and the solder resist pattern 23 is formed on the upper and lower portions of the original board to form a build-up multilayer printed circuit board. Complete

In the method of manufacturing a printed circuit board in which a via-hole is formed in the above-described copper clad laminate (CCL) by drilling, and a build-up layer is formed on the upper and lower surfaces, there is a limit to reducing the pitch of the internal via hole. There was a problem that the number of internal via holes is limited.

In addition, in the method of manufacturing a printed circuit board as described above, as shown in FIG. 2, the connection length of the inner via hole 14 is as long as the thickness of the copper-clad laminate, and the cross-sectional area is a donut shape, so that the electrical connection between layers is long. There was a problem of losing reliability.

In addition, in the method of manufacturing a printed circuit board as described above, in order to implement a stack via of the inner via hole, an additional process such as filling the via hole with conductive filling ink or forming a cap plating is performed. There has been a problem that the manufacturing process of the printed circuit board is complicated and the cost is increased.

The present invention provides a printed circuit board using an anisotropic conductive film that implements fine pitch of via holes and circuit patterns and is not limited to the number of via holes in order to solve the problems as described above, and a method of manufacturing the same.

The printed circuit board using the anisotropic conductive film according to the present invention is an anisotropic conductive film layer which is electrically conductive in a vertical direction at an inner via hole corresponding portion, and is formed on the anisotropic conductive film layer and interlayer electrical conduction is formed by the inner via hole corresponding portion. And a plating layer formed on an inner via hole corresponding portion on the circuit layer.

In addition, a method of manufacturing a two-layer printed circuit board using an anisotropic conductive film according to the present invention is a first step of forming a circuit pattern using a photolithography process on an anisotropic conductive film having a copper foil layer formed on top and bottom, on the circuit pattern A second step of forming a resist pattern according to a corresponding portion of the via hole, a third step of forming a protruding plating layer by removing the resist pattern after copper plating the recesses formed between the resist patterns, and heating the protruding plating layer And a fourth step of vertically electrically conducting an anisotropic conductive film portion corresponding thereto by pressing.

In addition, in the multilayer printed circuit board using the anisotropic conductive film according to the present invention, a first step of forming an inner circuit pattern using a photolithography process on a first anisotropic conductive film having copper foil layers formed on upper and lower portions thereof, and the inner circuit pattern A second step of forming a resist pattern according to an inner via hole corresponding portion on the third step; a third step of forming a protruding plating layer by peeling the resist pattern after copper plating is performed on the depressions formed between the resist patterns, and the protruding plating layer The fourth step of completing a base substrate by vertically conducting a portion of the anisotropic conductive film corresponding thereto by heating and pressing the second substrate, and laminating a second anisotropic conductive film on the upper and lower portions of the base substrate, and forming a copper foil layer on the second anisotropic conductive film. Stacking and forming an outer circuit pattern by a photolithography process, and forming a blind via hole on the outer circuit pattern. That is heated to a sixth step, the formed plating layer to form a plated layer with another photolithography process pressure comprises a seventh step of FIG barrel 2 as an anisotropic conductive film portion perpendicular to corresponding features.

In addition, in the method of manufacturing a multilayer printed circuit board using the anisotropic conductive film according to the present invention, a first step of forming an inner circuit pattern using a photolithography process on an anisotropic conductive film having copper foil layers formed on upper and lower portions thereof, and the inner circuit pattern A second step of forming a resist pattern according to a corresponding portion of the via hole on the second hole; a third step of forming a protruding plating layer by removing the resist pattern after copper plating the recesses formed between the resist patterns; A fourth step of completing a base substrate by vertically conducting a portion of the anisotropic conductive film corresponding thereto by heating and pressing, a fifth step of stacking an insulating layer on upper and lower portions of the base substrate and forming a blind via hole, and on the insulating layer Forming a seed layer thereon and forming an outer circuit pattern in a semi-additive manner. And a gong.

Hereinafter, a printed circuit board using the anisotropic conductive film according to the present invention and a manufacturing method thereof will be described in detail with reference to the accompanying drawings.

First, a configuration of a printed circuit board using an anisotropic conductive film according to the present invention will be described with reference to FIG. 3.

The printed circuit board using the anisotropic conductive film according to the present invention is composed of an anisotropic conductive film layer 110, a circuit layer 140, and a plating layer 160.

The anisotropic conductive film layer 110 is formed of an anisotropic conductive film and includes a section in which electrical conduction is performed vertically by partial heating pressure without via holes.

The anisotropic conductive film has a structure in which conductive particles are dispersed in an insulating adhesive film, and when heated and pressurized, the anisotropic conductive film is energized only in the direction of the electrode and has an anisotropic electrical conductivity having an insulating function between the electrode and the electrode.

In addition, anisotropic conductive films are mainly used in mounting technology for connecting LCD panels and driving circuit chips for LCDs used in TVs and computers according to anisotropic electrical conductivity characteristics.

The circuit layer 140 is formed of copper foil on the upper and lower portions of the anisotropic conductive film layer 110, and the portion in contact with the plating layer is pressed toward the anisotropic conductive film layer 110 by pressing.

The plating layer 160 is formed of copper foil in the via hole pattern on the circuit layer 140, and is pressed toward the circuit layer 140 by pressing.

A method of manufacturing a two-layer printed circuit board using an anisotropic conductive film according to a first embodiment of the present invention will be described with reference to FIG. 4.

First, as shown in FIG. 4A, an anisotropic conductive film 110 is provided.

 The anisotropic conductive film 110 has a structure in which conductive particles are dispersed in the insulating adhesive film, and when heated and pressurized, the anisotropic conductive film 110 is energized only in the direction of the electrode and has an anisotropic electrical conductivity having an insulating function between the electrode and the electrode.

The conductive particles basically consist of nickel (Ni), gold / polymer (Au / polymaer), silver (Ag) and the like, and the insulating material is composed of a thermosetting and thermoplastic insulating resin.

In addition, the anisotropic conductive film 110 is mainly used in a mounting technology for connecting an LCD panel and a driving circuit chip for a liquid crystal display (LCD) used in a TV or a computer according to anisotropic electrical conductivity characteristics.

Thereafter, as shown in FIG. 4B, the copper foil layer 120 is interposed between upper and lower portions of the anisotropic conductive film 110.

The copper foil layer 120 is for forming the circuit pattern mentioned later, and is formed by adhering a thin copper foil.

In this case, after the electroless copper plating is performed on the anisotropic conductive film 110 using a precipitation reaction instead of the copper foil layer 120, electrolytic copper plating may be performed by electrolysis to use a plating layer.

The reason why electroless copper plating and electrolytic copper plating are performed together is that electroless copper plating alone cannot be used as it is because of its thin thickness and physical properties, and the electroless copper plating film forms a conductive film required for electrolytic copper plating.

As described above, after the copper foil layer 120 is interposed between the upper and lower portions of the anisotropic conductive film 110, an etching resist pattern 130 for forming a circuit pattern is formed as shown in FIG. 4C.

Here, in order to form the etching resist pattern 130, the circuit pattern printed on the mask must be transferred onto the substrate. There are various methods for transferring, but the most commonly used method is a method of transferring a circuit pattern printed on a mask by ultraviolet light to a dry film using a photosensitive dry film.

Thereafter, as shown in FIG. 4D, copper foil etching is performed and the etching resist pattern 130 is removed to form a circuit pattern.

That is, the dry film to which the circuit pattern is transferred serves as an etching resist. When the etching process is performed on the copper foil, the copper foil layer 120 in the region where the etching resist pattern 103 is not formed is removed to have a predetermined shape. The circuit pattern 140 is provided.

As described above, after the circuit pattern is formed, the resist pattern 150 for the connection line pattern is formed as shown in FIG. 4E.

Here, in order to form the resist pattern 150, portions except for the connection line pattern printed on the mask must be transferred onto the substrate. There are various methods of transferring, but the most commonly used method is a method of transferring a portion printed on a mask by ultraviolet light to a dry film using a photosensitive dry film.

Thereafter, as shown in FIG. 4F, electrolytic copper plating is performed between the resist patterns 150, and the resist pattern 150 is removed to complete the connecting line pattern 160.

That is, the dry film, except for the connecting line pattern 160, is printed to serve as the resist pattern 150. When the electrolytic copper plating is performed between the resist patterns 150 and the dry film is removed, the connecting line pattern 160 having a predetermined shape is formed. ) Is formed.

Here, the connection line pattern 160 is a pattern of a line electrically connected between both circuit patterns and is the same as the via hole position formed in the conventional anisotropic conductive film layer.

As described above, after completing the connecting line pattern 160, the connecting line pattern 160 is heated and pressurized as shown in FIG. 4G.

When the predetermined heat is applied, the anisotropic conductive film 110 is in a semi-cured state. When a predetermined pressure is applied, the connection line pattern 160 presses the circuit pattern 140 and the pressurized circuit pattern 140 is again anisotropically conductive. The density of the pressurized anisotropic conductive film 110 is increased by pressing the film 110, and electrical conduction is vertically performed by the conductive particles.

At this time, a portion in which electrical conduction occurs in the anisotropic conductive film 110 becomes a connection line for electrically connecting the circuit patterns 140 on both sides.

Thereafter, as shown in FIG. 4H, the solder resist pattern 170 is formed and surface treatment is performed using electroless nickel / gold plating to complete a two-layer printed circuit board using an anisotropic conductive film.

The solder resist pattern 170 protects the circuit pattern and prevents defects due to short circuits between wirings and problems of incorrect connection when mounting an electronic component on a substrate. To prevent soldering and to improve the solderability of components to be mounted, and to impart good conductivity.

Here, the solder resist pattern 170 is formed by applying a solder resist and exposing and developing a mask in which the solder resist pattern is output.

The resist ink for solder resist is PSR (Photo imageable Solder Resist Ink), which is green and is made of heat-resistant resin that can withstand the melting temperature of solder.

A method of manufacturing a multilayer printed circuit board using an anisotropic conductive film according to a second embodiment of the present invention will be described with reference to FIG. 5.

First, as shown in FIG. 5A, a first copper foil layer 220 is provided to the first anisotropic conductive film 210.

 The anisotropic conductive film 210 has a structure in which conductive particles are dispersed in an insulating adhesive film, and when heated under pressure, the anisotropic conductive film 210 is energized only in an electrode direction and has an anisotropic electrical conductivity characteristic having an insulating function between the electrode and the electrode.

The conductive particles basically consist of nickel (Ni), gold / polymer (Au / polymaer), silver (Ag) and the like, and the insulating material is composed of a thermosetting and thermoplastic insulating resin.

The 1st copper foil layer 220 is for forming the circuit pattern mentioned later, and is formed by adhering a thin copper foil.

In this case, after the electroless copper plating is performed on the anisotropic conductive film 210 by using the precipitation reaction instead of the first copper foil layer 220, the plating layer may be used by performing electrolytic copper plating by electrolysis.

Thereafter, as illustrated in FIG. 5B, an inner layer circuit pattern 230 is completed by forming an etching resist pattern, performing an etching process, and then removing the etching resist pattern.

Here, in order to form the etching resist pattern, the inner circuit pattern 230 printed on the mask must be transferred onto the substrate. There are various methods of transferring, but the most commonly used method is a method of transferring an inner circuit pattern printed on a mask by ultraviolet light to a dry film using a photosensitive dry film.

That is, the dry film to which the inner circuit pattern 230 is transferred serves as an etching resist. When the etching process is performed on the copper foil, the copper foil layer 220 in the region where the etching resist pattern is not formed is removed to have a predetermined shape. The inner circuit pattern 230 is completed.

As described above, after completing the inner circuit pattern 230, as shown in FIG. 5C, a resist pattern is formed on the inner circuit pattern 230, copper plating is performed, and the resist pattern is removed to remove the first connection line pattern ( 240).

Here, in order to form a resist pattern, portions other than the connection line pattern printed on the mask must be transferred onto the substrate. There are various methods of transferring, but the most commonly used method is a method of transferring a portion printed on a mask by ultraviolet light to a dry film using a photosensitive dry film.

That is, the dry film in which the portion except the first connection line pattern 240 is printed serves as a resist pattern. When the electrolytic copper plating is performed between the resist patterns and the dry film is removed, the first connection line pattern 240 having a predetermined shape is formed. Is formed.

Here, the first connection line pattern 240 is a pattern of a line electrically connected between the inner circuit patterns 230 and is the same as the via hole position formed in the conventional anisotropic conductive film layer.

Subsequently, as illustrated in FIG. 5D, the first connection line pattern 240 is heated and pressurized to complete the base substrate 250 that is electrically connected between the inner circuit patterns 230.

When a predetermined heat is applied, the first anisotropic conductive film 210 is in a semi-cured state, and when a predetermined pressure is applied, the first connection line pattern 240 presses the inner circuit pattern 230 and presses the pressed inner layer circuit pattern ( 230 again pressurizes the first anisotropic conductive film 210 so that the density of the pressurized first anisotropic conductive film 210 is increased so that electrical conduction is vertically conducted by the conductive particles.

In this case, a portion in which electrical conduction occurs in the first anisotropic conductive film 210 becomes a connection line for electrically connecting the inner circuit pattern 230.

After the base substrate 250 is completed as described above, as illustrated in FIG. 5E, the second anisotropic conductive film 260 is stacked on the upper and lower surfaces of the base substrate 250.

The second anisotropic conductive film 260 is then electrically insulated in the vertical direction by the heating and pressing process while maintaining the insulating state in the horizontal direction to insulate the interlayer.

Thereafter, as illustrated in FIG. 5F, the second copper foil layer 270 is stacked on the second anisotropic conductive film 260.

In this case, after the electroless copper plating is performed on the second anisotropic conductive film 260 by using the precipitation reaction instead of the second copper foil layer 270, electrolytic copper plating may be performed by electrolysis to use the plating layer.

As described above, after the second copper foil layer 270 is stacked, an outer circuit pattern 280 is formed by a photolithography process using an etching resist pattern as illustrated in FIG. 5G.

Subsequently, as shown in FIG. 5H, the second interconnection line pattern 290 is formed by forming a resist pattern on the outer circuit pattern 280, performing copper plating, and removing the resist pattern.

Here, the second connection line pattern 290 is a pattern of a line electrically connecting the outer circuit pattern 280 and the inner layer circuit pattern 230 to be the same as the position of the blind via hole formed in the conventional insulating layer.

As described above, after completing the second connection line pattern 290, the second connection line pattern 290 is heated and pressurized as shown in FIG. 5I.

When a predetermined heat is applied, the second anisotropic conductive film 260 is in a semi-cured state, and when a predetermined pressure is applied, the second connection line pattern 290 presses the outer circuit pattern 280 and presses the pressed outer circuit pattern ( 280 again presses the second anisotropic conductive film 280, so that the density of the pressurized anisotropic conductive film 280 is increased so that the conductive particles are perpendicularly formed between the outer layer circuit pattern 280 and the inner layer circuit pattern 230 by the conductive particles. Electrical conduction is made.

Subsequently, as shown in FIG. 5J, the solder resist pattern 300 is formed and surface treatment is performed using electroless nickel / gold plating to complete a multilayer printed circuit board using an anisotropic conductive film.

The solder resist pattern 300 protects the circuit pattern and prevents defects due to short circuits between wirings and problems of misconnection when the electronic component is mounted on a substrate. To prevent soldering and to improve the solderability of components to be mounted, and to impart good conductivity.

Here, the solder resist pattern 300 is formed by applying a solder resist and exposing and developing a mask in which the solder resist pattern is output.

In this case, the second connection line pattern 290 may be formed by a predetermined height without forming the solder resist pattern 300 on the substrate, and thus may be used as a flip chip bump.

A method of manufacturing a multilayer printed circuit board using an anisotropic conductive film according to a third embodiment of the present invention will be described with reference to FIG. 6.

First, as shown in FIG. 6A, an anisotropic conductive film 310 is provided through a copper foil layer 320.

 The anisotropic conductive film 310 is a structure in which conductive particles are dispersed in an insulating adhesive film, and when heated and pressurized, the anisotropic conductive film 310 is energized only in an electrode direction and has an anisotropic electrical conductivity having an insulating function between the electrode and the electrode.

The conductive particles basically consist of nickel (Ni), gold / polymer (Au / polymaer), silver (Ag) and the like, and the insulating material is composed of a thermosetting and thermoplastic insulating resin.

The copper foil layer 320 is for forming the circuit pattern mentioned later, and is formed by adhering a thin copper foil.

In this case, after the electroless copper plating is performed on the anisotropic conductive film 310 by using the precipitation reaction instead of the copper foil layer 320, the plating layer may be used by performing electrolytic copper plating by electrolysis.

Thereafter, as illustrated in FIG. 6B, the inner circuit pattern 330 is completed using a photolithography process.

As described above, after completing the inner circuit pattern 330, as shown in FIG. 6C, the resist pattern is formed on the inner circuit pattern 330, copper plating is performed, and then the resist pattern is removed to remove the resist pattern. To form.

That is, when electrolytic copper plating is performed between the resist patterns except for the connection line pattern 340 and the resist pattern is removed, the connection line pattern 340 having a predetermined shape is formed.

Subsequently, as illustrated in FIG. 6D, the connection line pattern 340 is heated and pressurized to complete the base substrate 350 that is electrically connected between the inner circuit patterns 330.

When the predetermined heat is applied, the anisotropic conductive film 310 is in a semi-cured state, and when a predetermined pressure is applied, the connection line pattern 340 presses the inner layer circuit pattern 330 and the pressurized inner layer circuit pattern 330 again. The density of the pressurized anisotropic conductive film 310 is increased by pressing the anisotropic conductive film 310, so that electrical conduction is vertically performed by the conductive particles.

In this case, a portion where electrical conduction occurs in the anisotropic conductive film 310 becomes a connection line for electrically connecting the inner circuit pattern 330.

As described above, after the base substrate 350 is completed, the insulating layer 360 is laminated on both surfaces of the base substrate 350 as shown in FIG. 6E.

Here, the insulating layer 360 is an insulating material in the form of a film, and serves as an insulator between the circuit layers.

Thereafter, as illustrated in FIG. 6F, the blind via hole 370 serving as an electrical connection between the inner layer and the outer layer is processed.

In this case, although the blind via hole 370 may use mechanical drilling, it is preferable to use YAG (Yttrium Aluminum Garnet) laser or CO2 laser because it requires more precise processing than when processing the through hole. The YAG laser is a laser capable of processing both a copper foil layer and an insulating layer, and the CO2 laser is a laser capable of processing only an insulating layer.

After processing the blind via hole 370 as described above, as shown in FIG. 6G, electroless copper plating is performed on the insulating layer 360 to form a seed layer 380 for forming an outer circuit pattern.

In this case, the metal forming the seed layer 380 is not limited to copper (Cu), but may be formed using a metal and a metal oxide different from copper, more specifically, Ni, Sn, SnO, or the like.

Thereafter, as shown in FIG. 6H, the outer circuit pattern forms a resist pattern 390 for forming.

Here, in order to form the resist pattern 390, portions except for the connection line pattern printed on the mask must be transferred onto the substrate. There are various methods of transferring, but the most commonly used method is a method of transferring a portion printed on a mask by ultraviolet light to a dry film using a photosensitive dry film.

After forming the resist pattern 390 as described above, as shown in FIG. 6I, an electrolytic copper plating is performed, the resist pattern 390 is removed, and the open seed layer 380 is etched to thereby etch the outer layer circuit pattern 400. To complete).

Thereafter, as shown in FIG. 6I, a solder resist pattern 410 is formed to protect the outer circuit pattern 400 and to prevent short circuits and misconnections between the wirings, and to perform surface treatment using electroless nickel / gold plating. The multilayer printed circuit board using the conductive film is completed.

As described above, according to the printed circuit board and the manufacturing method using the anisotropic conductive film according to the present invention, the density of the circuit per unit area is greatly increased by realizing the electrical conduction between layers using the characteristics of the anisotropic conductive film without forming via holes. In addition to significantly improving the electrical performance of the printed circuit board, the signal delay caused by the inner layer via hole is greatly reduced.

Herein, the present invention described above has been described with reference to preferred embodiments, but those skilled in the art can variously modify the present invention without departing from the spirit and scope of the present invention as set forth in the claims below. It will be appreciated that this can be changed.

Claims (15)

An anisotropic conductive film layer that is electrically conductive in a vertical direction at a corresponding portion of the inner via hole; A circuit layer formed on the anisotropic conductive film layer and being electrically connected between layers by the corresponding portion of the inner via hole; And Plating layer formed in the corresponding portion of the inner via hole on the circuit layer Printed circuit board using an anisotropic conductive film comprising a. The method of claim 1, The anisotropic conductive film layer is a printed circuit board using an anisotropic conductive film, characterized in that the circuit layer penetrates to a predetermined depth according to the corresponding portion of the via hole. A first step of forming a circuit pattern on the anisotropic conductive film having copper foil layers formed on upper and lower portions thereof by using a photolithography process; A second step of forming a resist pattern corresponding to a via hole corresponding portion on the circuit pattern; A third step of forming a protruding plating layer by removing the resist pattern after copper plating is performed on the depressions formed between the resist patterns; And A fourth step of heating and pressing the protruding plating layer to vertically electrically conduct the corresponding anisotropic conductive film portion; Printed circuit board manufacturing method using an anisotropic conductive film comprising a. The method of claim 3, A fifth step of forming a solder resist pattern on the protruding plating layer Printed circuit board manufacturing method using an anisotropic conductive film, characterized in that it further comprises. The method of claim 3, The method of forming a circuit pattern using the photolithography process of the first step is Step 1-1 to coat the dry film (D / F) cured by ultraviolet light on the copper foil layer; First to second steps of matching a mask having a predetermined circuit pattern on the dry film; Steps 1 to 3 performing a curing treatment on the dry film by performing ultraviolet irradiation through the mask; A first to fourth step of etching the opened copper foil layer by removing the dry film uncured by the ultraviolet irradiation; And Steps 1-5 to form a predetermined circuit pattern by removing the dry film coated on the non-etched copper foil layer Printed circuit board manufacturing method using an anisotropic conductive film comprising a. A first step of forming an inner circuit pattern on the first anisotropic conductive film having a copper foil layer formed on upper and lower portions by using a photolithography process; Forming a resist pattern corresponding to an inner via hole corresponding portion on the inner circuit pattern; Performing a copper plating process on the recesses formed between the resist patterns, and then peeling the resist pattern to form a protruding plating layer; A fourth step of heating and pressing the protruding plating layer to vertically conduct a portion of the anisotropic conductive film corresponding thereto to complete the base substrate; A fifth step of forming an outer layer circuit pattern by a photolithography process by laminating a second anisotropic conductive film on and under the base substrate and laminating a copper foil layer on the second anisotropic conductive film; Forming a plating layer corresponding to a blind via hole corresponding portion on the outer circuit pattern by a photolithography process; A seventh step of heating and pressing the formed plating layer to vertically conduct a second anisotropic conductive film portion corresponding thereto; Multi-layer printed circuit board manufacturing method using an anisotropic conductive film comprising a. The method of claim 6, An eighth step of forming a solder resist pattern on the protruding plating layer; Multi-layer printed circuit board manufacturing method using an anisotropic conductive film, characterized in that it further comprises. The method of claim 6, The method of forming the inner circuit pattern using the photolithography process of the first step is Step 1-1 to coat the dry film (D / F) cured by ultraviolet light on the copper foil layer; First to second steps of matching a mask having a predetermined inner layer circuit pattern formed on the dry film; Steps 1 to 3 performing a curing treatment on the dry film by performing ultraviolet irradiation through the mask; A first to fourth step of etching the opened copper foil layer by removing the dry film uncured by the ultraviolet irradiation; And Steps 1 to 5 to form a predetermined inner layer circuit pattern by removing the dry film coated on the non-etched copper foil layer Multi-layer printed circuit board manufacturing method using an anisotropic conductive film comprising a. The method of claim 6, The method of forming the outer circuit pattern using the photolithography process of the fifth step Step 5-1 of coating a dry film (D / F) to be cured by ultraviolet light on the copper foil layer; Step 5-2 of matching the mask on which the predetermined circuit pattern is formed on the dry film; Step 5-3 of performing a curing treatment on the dry film by performing ultraviolet irradiation through the mask; A fifth step of etching the copper foil layer opened by removing the uncured dry film by the ultraviolet irradiation; And Steps 5-5 to form a predetermined outer layer circuit pattern by removing the dry film coated on the non-etched copper foil layer Multi-layer printed circuit board manufacturing method using an anisotropic conductive film comprising a. The method of claim 6, The method of forming the plating layer of the sixth step A step 6-1 of forming a resist pattern according to a blind via hole pattern on the outer circuit pattern; And Step 6-2 of forming a protruding plating layer by peeling the resist pattern after copper plating is performed on the depressions formed between the resist patterns. Method of manufacturing a multilayer printed circuit board using an anisotropic conductive film comprising a. A first step of forming an inner circuit pattern using a photolithography process on an anisotropic conductive film having copper foil layers formed on upper and lower portions thereof; Forming a resist pattern corresponding to a via hole corresponding portion on the inner circuit pattern; A third step of forming a protruding plating layer by removing the resist pattern after copper plating is performed on the depressions formed between the resist patterns; A fourth step of heating and pressing the protruding plating layer to vertically conduct a portion of the anisotropic conductive film corresponding thereto to complete the base substrate; Stacking an insulating layer on upper and lower portions of the base substrate and forming a blind via hole; And A sixth step of forming a seed layer on the insulating layer and forming an outer circuit pattern in a semi-additive manner; Method of manufacturing a multilayer printed circuit board using an anisotropic conductive film comprising a. The method of claim 11, A seventh step of forming a solder resist pattern on the outer circuit pattern Multi-layer printed circuit board manufacturing method using an anisotropic conductive film, characterized in that it further comprises. The method of claim 11, The method of forming the inner circuit pattern using the photolithography process of the first step is Step 1-1 to coat the dry film (D / F) cured by ultraviolet light on the copper foil layer; First to second steps of matching a mask having a predetermined inner layer circuit pattern formed on the dry film; Steps 1 to 3 performing a curing treatment on the dry film by performing ultraviolet irradiation through the mask; A first to fourth step of etching the opened copper foil layer by removing the dry film uncured by the ultraviolet irradiation; And Steps 1 to 5 to form a predetermined inner layer circuit pattern by removing the dry film coated on the non-etched copper foil layer Multi-layer printed circuit board manufacturing method using an anisotropic conductive film comprising a. The method of claim 11, The method of forming the outer circuit pattern in the semi-additive method of the sixth step Step 6-1 coating the dry film (D / F) cured by ultraviolet irradiation on the seed layer; Step 6-2 of matching the mask on which the predetermined circuit pattern is formed on the dry film; Step 6-3 to perform a curing treatment for the dry film by performing ultraviolet irradiation through the mask; A step 6-4 of removing the uncured dry film by the ultraviolet irradiation to open the seed layer; A step 6-5 of performing electrolytic copper plating on the open seed layer to form a plating layer; A sixth to sixth step of forming a predetermined outer layer circuit pattern by removing the dry film existing outside the region where the plating layer is formed; And Steps 6-7 of etching to remove the seed layer existing in the open region where the outer circuit pattern is not formed. Multi-layer printed circuit board manufacturing method using an anisotropic conductive film comprising a. The method of claim 1, The plating layer is a printed circuit board using an anisotropic conductive film, characterized in that pressed to the circuit layer to some extent.

Images