JPH10294548A - Manufacture of printed wiring board and printed wiring board using the method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a manufacturing method which can reliably mass-produce printed wiring boards with high precision and high density at low cost. SOLUTION: A master substrate 1 which has a pattern electrode layer 3 formed in a specific shape is manufactured first. On the master board 1, a peeling layer 4 is formed of a water-repellent thin film. Then an electrodeposited resin thin film 5 is formed on the peeling layer 4 by electrodeposition. On this electrodeposited resin thin film 5, a wiring conductor 6 is formed of a metal film by plating. The electrodeposited resin film 5 is impregnated with water. The deposits of the laminated electrodeposited resin thin film 5 and wiring conductor 6 are peeled off the master board 1 through a sticky layer or adhesive layer 10 and transferred to a target board 8.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a variety of wirings such as high-density printed wiring boards, multilayer printed wiring boards and flexible printed wiring boards incorporated in semiconductor packaging such as IC card terminals and electronic equipment such as portable information terminals. The present invention relates to a method for manufacturing a printed wiring board that can be used when forming a board.

[0002]

2. Description of the Related Art As a conventional method of manufacturing a printed wiring board, a predetermined insulating circuit pattern is formed on a copper foil on the surface of a copper-clad board, and this is used as an etching mask.
Subtract method of removing unnecessary parts by etching to form wiring conductors, or applying a catalyst to the surface of an insulating substrate not covered with copper foil, forming a predetermined insulating circuit pattern, and plating this There is an additive method in which a wiring conductor is formed by electroless copper plating using a mask.

On the other hand, as a method of forming an insulating circuit pattern on a substrate surface, there is a photolithography method which is widely used in a semiconductor process and exposes and develops a photosensitive resist. This photosensitive resist exposure apparatus is a precision machine and has a highly adjusted optical system, and can form a high-resolution pattern. However, the exposure apparatus is an extremely expensive apparatus, and as a result, the product price has been expensive. On the other hand, as a method of forming an insulating circuit pattern at low cost, there is a printing method of directly forming a pattern on a substrate surface. The printing method includes an offset printing method, a screen printing method, and the like. In any of these methods, the pattern accuracy at the time of mass production is limited to 100 μm due to the fluidity of the ink and the poor transfer of the ink. The reproducibility was not good, and it was not suitable for forming a high-resolution pattern.

[0004] In recent years, as the frequency of semiconductor devices has been increased and electronic devices have been downsized and highly integrated, there has been a demand for thinner printed circuit boards, higher densities, and multilayered printed wiring boards. For this reason, photolithography, which has excellent quality for high integration, has been mainly used, but it is expensive, and a method of manufacturing a printed wiring board that enables high integration and low cost is desired. Was rare.

In order to reduce the cost of the printed wiring board, the following ideas have been devised. First, Japanese Patent Application Laid-Open No. 52-50572 discloses a method in which a wiring conductor is formed on another substrate having excellent surface properties, and then separated and transferred to a flexible substrate having an adhesive layer on the surface. . In this publication, after an insulating circuit pattern is formed on a metal conductive substrate having a mirror surface, copper plating is applied to a portion where the metal conductive substrate is exposed without being covered with the insulating circuit pattern. After the formation of the wiring conductor, the wiring conductor is peeled and transferred onto the flexible substrate by the adhesive layer on the surface of the flexible substrate to form a printed wiring board. However, in this method, the wiring conductor is adhered to the flexible substrate and mechanically peeled and transferred, so the insulating circuit pattern itself may be peeled off by the adhesive layer on the flexible substrate surface, and the insulating circuit pattern is repeatedly used. However, there is a problem that it is necessary to frequently form an insulating circuit pattern by photolithography. Further, as the density of the wiring conductor increases, the area of the wiring conductor in contact with the adhesive layer decreases, and it is expected that complete peeling transfer of the wiring conductor is difficult.

Next, Japanese Patent Application Laid-Open No. 58-168296 was devised in order to enable complete peeling transfer of a high-density wiring conductor. In this publication, first, a thick copper plating film having a thickness that can be handled as a single body is formed on a metal conductive substrate,
After forming an insulating circuit pattern on the thick copper plating film by a photolithography method, in a portion where the thick copper plating film is exposed without being covered with the insulating circuit pattern,
After forming a wiring conductor by laminating by corrosion-resistant metal plating and copper electroplating, this wiring conductor is peeled and transferred together with the copper plating thick film onto the flexible substrate by the adhesive layer on the flexible substrate surface, thereby forming a high-density wiring conductor. Complete peeling transfer becomes possible, and then the copper plating thick film is etched away to form a printed wiring board. However, it is necessary to form an insulating circuit pattern by photolithography every time, and there is still a problem of reducing the cost of a printed wiring board.

[0007]

In the above-mentioned methods for manufacturing a printed wiring board, none of the publications can satisfy both the complete peeling transfer of a high-density wiring conductor and the repeated use of an insulating circuit pattern. . Further, by repeating the electroplating and the peeling transfer, the surface properties of the metal conductive substrate which had been a mirror surface deteriorated, and the surface had to be polished again for repeated use. Therefore, there is a need for a method of manufacturing a printed wiring board that can form a high-precision, high-density wiring conductor that is more inexpensive, has good yield, and is excellent in mass productivity. Also,
Insulating circuit patterns and metal conductive substrates can be repeatedly used, and a longer life is also required.

An object of the present invention is to provide a method of manufacturing a printed wiring board capable of mass-producing high-precision, high-density printed wiring boards at a low cost and with high reliability, and to provide a printed wiring board using the same.

[0009]

In order to solve the above-mentioned problems, a method of manufacturing a printed wiring board according to the present invention comprises the steps of: forming a pattern electrode layer having a predetermined shape on a substrate; A release layer forming step of forming a release layer made of a water-repellent thin film, an electrodeposition resin thin film forming step of forming an electrodeposition resin thin film on the release layer by an electrodeposition method, and a plating method on the electrodeposition resin thin film A wiring conductor forming step of forming a wiring conductor made of a metal film, a water impregnating step of impregnating the electrodeposited resin thin film with moisture, and adhering the electrodeposited product obtained by laminating the electrodeposited resin thin film and the wiring conductor. A separation transfer step of separating the master substrate through the layer or the adhesive layer and transferring the master substrate to the transfer substrate. With this configuration, when the electrodeposited resin thin film is impregnated with moisture in the water-containing step, the adhesive strength of the electrodeposited resin thin film to the release layer is significantly reduced because the release layer is water-repellent.
The electrodeposited resin thin film and wiring conductor laminated on the adhesive layer of the substrate to be transferred from the master substrate can be completely and completely peeled and transferred, and excellent mass productivity with high-definition and high-density wiring conductors Printed wiring boards can be manufactured.

According to another aspect of the present invention, there is provided a printed wiring board including a substrate, a wiring conductor formed on the substrate, a through hole penetrating the substrate, and a hole introduced into the through hole. And a conductive material, wherein the conductive material is electrically connected to the wiring conductor. The printed wiring board is manufactured by the above-described method for manufacturing a printed wiring board. With this configuration, a high-definition and high-density wiring conductor can be provided at a low price.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The method for manufacturing a printed wiring board according to claim 1 of the present invention comprises a master substrate manufacturing step of manufacturing a master substrate having a pattern electrode layer of a predetermined shape formed on a surface thereof; A release layer forming step of forming a release layer made of a water-repellent thin film thereon, an electrodeposition resin thin film forming step of forming an electrodeposition resin thin film on the release layer by an electrodeposition method, and A wiring conductor forming step of forming a wiring conductor made of a metal film by a plating method, a water impregnating step of impregnating the electrodeposited resin thin film with moisture, and an electrodeposit formed by laminating the electrodeposited resin thin film and the wiring conductor. And a separation transfer step of separating the master substrate from the master substrate via the adhesive layer or the adhesive layer and transferring the master substrate to the transfer substrate. With this configuration, when the electrodeposited resin thin film is impregnated with moisture in the water-containing step, the adhesive strength of the electrodeposited resin thin film to the release layer is significantly reduced because the release layer is water-repellent. This has the effect that it is possible to reliably and completely separate and transfer the electrodeposit from the substrate on the adhesive layer of the substrate to be transferred onto which the electrodeposited resin thin film and the wiring conductor are laminated. Thereby, since the peeling transfer is performed in a state in which the adhesion of the electrodeposited resin thin film to the peeling layer is significantly reduced, the peeling transfer and the patterning layer of the master substrate are not damaged during the peeling transfer. Wiring conductors of the same shape can be formed with extremely high reproducibility using a substrate, and the master substrate can be used repeatedly to extend the service life. In addition, since the adhesion of the electrodeposited resin thin film to the release layer can be weakened, an adhesive layer having a low adhesive strength can be used for the substrate to be transferred, and the master substrate and the substrate to be transferred are forcibly applied during the release transfer. Since the wiring conductor is not peeled off, it has the effect of preventing the shape of the wiring conductor from being broken or damaged. Furthermore, the pattern electrode layer that forms the electrodeposited resin thin film and the wiring conductor can be formed very densely and with high density on the master substrate by photolithography, etc. In addition, it has an effect that it can be manufactured with good mass productivity.

According to a second aspect of the present invention, in the method for manufacturing a printed wiring board according to the first aspect of the present invention, the master substrate manufacturing step includes the step of forming a conductive layer on an insulating substrate. And an electrode layer forming step of forming a pattern electrode layer of a wiring conductor having a predetermined shape by etching the conductive layer to produce a master substrate,
Since the pattern shape of the electrode layer of the master substrate can be formed by etching, it has an effect that it is extremely easy and easy to form.

According to a third aspect of the present invention, in the method for manufacturing a printed wiring board according to the first aspect of the present invention, the master substrate manufacturing step includes the step of forming a conductive layer on an insulating substrate. And an electrode layer forming step of forming an insulating layer on the conductive layer, forming a negative pattern electrode layer of a wiring conductor having a predetermined shape by etching the insulating layer, and manufacturing a master substrate. This has the effect that it is possible to design a wiring conductor with a high degree of freedom.

According to a fourth aspect of the present invention, in the method for manufacturing a printed wiring board according to the first aspect, the master substrate forming step includes forming an insulating layer on a conductive substrate, and forming the insulating layer on the conductive substrate. This is an electrode layer forming step of forming a negative pattern electrode layer of a wiring conductor having a predetermined shape by etching to produce a master substrate, and has an effect that a wiring conductor having a high degree of freedom can be designed.

According to a fifth aspect of the present invention, there is provided a method of manufacturing a printed wiring board according to any one of the first to fourth aspects, wherein the insulating substrate serving as a master substrate is provided. One of the substrate and the transferred substrate is made of a flexible film or the like, and the other of the insulating substrate or the transferred substrate is made of a rigid glass or the like. One of them has flexibility, so that it can be easily peeled off after the master substrate and the transferred substrate are tightly joined, and the electrodeposited resin thin film and the wiring conductor on the master substrate are laminated. The deposited material can be easily peeled and transferred to the substrate to be transferred.

According to a seventh aspect of the present invention, in the method for manufacturing a printed wiring board according to the fourth aspect, the master substrate forming step includes forming an insulating layer on a flexible metal foil, This is an electrode layer forming step of forming a negative pattern electrode layer of a wiring conductor having a predetermined shape by insulating layer etching to produce a master substrate, and since the master substrate has flexibility, the master substrate It has the effect of being able to be easily peeled off after the transferred substrate is tightly joined, and the electrodeposited resin thin film and the wiring conductor on the master substrate can be easily separated and transferred to the transferred substrate. .

According to a eighth aspect of the present invention, there is provided a method of manufacturing a printed wiring board according to any one of the first to seventh aspects.
In the invention described in the above, the electrode layer of the master substrate is made of a material having corrosion resistance to an etchant of the metal film to be the wiring conductor, and the metal film to be the wiring conductor remaining on the master substrate is etched. At the time of removal, the electrode layer on the master substrate has an effect of not being etched by the etchant, and the reproduction of the master substrate can be facilitated.

According to a ninth aspect of the present invention, there is provided a method of manufacturing a printed wiring board according to any one of the first to eighth aspects.
In the invention described in the above, the release layer forming step comprises a release layer forming step of forming a release layer formed of a water-repellent thin film composed of a metal film containing graphite fluoride particles on the master substrate, It has an effect that a conductive metal film and graphite fluoride particles such as polytetrafluoroethylene having water repellency can be easily formed simultaneously by a plating method or the like.

According to a tenth aspect of the present invention, in the method of manufacturing a printed wiring board according to any one of the first to eighth aspects, the step of forming a release layer comprises the steps of: It consists of a release layer forming step of forming a release layer composed of a water-repellent thin film composed of a graphite fluoride thin film. The water-repellent thin film having conductivity in a liquid because of its thinness is easily formed by a sputtering method or the like. And an effect that the film thickness can be controlled with high accuracy.

[0020] In the method for manufacturing a printed wiring board according to claim 11 of the present invention, in the invention according to any one of claims 1 to 8, the step of forming a release layer is performed on the master substrate. It consists of a release layer forming step of forming a release layer consisting of a water-repellent thin film composed of a fluorine-based coating agent, and a water-repellent thin film of fluorine oil or the like which is conductive in a liquid because it is thin, such as dip coating. Thus, it is possible to easily form the release layer even when the master substrate is reused.

According to a twelfth aspect of the present invention, in the method of manufacturing a printed wiring board according to any one of the first to eighth aspects, the step of forming a release layer comprises the steps of: The method comprises a release layer forming step of forming a release layer composed of a water-repellent thin film composed of perfluoropolyethylene having a silicon-based compound or a titanium-based compound as a terminal group. Easily and uniformly forms a water-repellent thin film of perfluoropolyethylene that is conductive in liquid because it is thin because the group has the property of easily adhering to the electrode layer etc. on the master plate And when the master substrate is reused, the release layer can be easily regenerated.

According to a thirteenth aspect of the present invention, in the method for manufacturing a printed wiring board according to any one of the tenth to twelfth aspects, the release layer has a thickness of 5 nm or more and 100 nm or less. In a release layer made of a fluorine-based compound having low conductivity, the electrodeposition resin is kept in a liquid while maintaining water repellency for weakening the adhesion of the electrodeposition resin thin film to the release layer. Has an effect that the release layer can be provided with such a degree of conductivity as to allow electrodeposition.

According to a fourteenth aspect of the present invention, there is provided a method of manufacturing a printed wiring board according to any one of the first to thirteenth aspects, wherein an electrodeposited resin thin film is formed by an electrodeposition method. And has an effect that a high quality electrodeposited resin thin film can be efficiently formed.

According to a fifteenth aspect of the present invention, in the method for manufacturing a printed wiring board according to any one of the first to fourteenth aspects, the electrodeposited resin thin film has a thickness of 50%.
The thickness is not less than 500 nm and not more than 500 nm, and in the electrodeposited resin thin film having low conductivity, while maintaining the water content for weakening the adhesion of the electrodeposited resin thin film to the release layer, the wiring conductor is This has the effect that conductivity in a liquid that allows plating can be imparted to the electrodeposited resin thin film.

According to a sixteenth aspect of the present invention, in the method for manufacturing a printed wiring board according to any one of the first to fifteenth aspects, the wiring conductor forming step is performed by a plating method. It is characterized by forming a conductor, and has an effect that a high-quality wiring conductor can be formed efficiently.

According to a method of manufacturing a printed wiring board as set forth in claim 17 of the present invention, in the invention as set forth in any one of claims 1 to 16, the water-containing step includes the step of adding 30 minutes to the electrodeposited resin thin film.
It is comprised of a water impregnation step of impregnating hot water at a temperature of not less than 80 ° C. and not less than 80 ° C. It is possible to sufficiently impregnate the inside of the electrodeposited resin thin film while promoting the evaporation of the water on the wiring conductor surface, An electrodeposit having the electrodeposited resin thin film and the wiring conductor laminated thereon can be more easily separated from the master substrate, and the adhesion of the wiring conductor to the substrate to be transferred can be improved.

[0027] In the method for manufacturing a printed wiring board according to claim 18 of the present invention, in the invention according to any one of claims 1 to 17, the transfer-receiving surface of the transfer-receiving substrate has adhesiveness. And has an effect that the adhesion of the wiring conductor to the substrate to be transferred can be improved.

According to a nineteenth aspect of the present invention, in the method for manufacturing a printed wiring board according to any one of the first to seventeenth aspects, the substrate to be transferred is formed on the surface to be transferred. In this case, the adhesive layer is disposed on the substrate, and has an effect that the adhesiveness of the wiring conductor to the substrate to be transferred can be improved.

According to a twentieth aspect of the present invention, in the method for manufacturing a printed wiring board according to any one of the first to eighteenth aspects, the printed circuit board is provided at a position corresponding to the wiring conductor. A step of forming a through-hole in the transfer substrate; and a step of introducing a conductive material into the through-hole in the step of forming the through-hole. Has a function of obtaining a printed wiring board having a high density.

According to a twenty-first aspect of the present invention, in the method for manufacturing a printed wiring board according to the nineteenth aspect, a through hole is formed in the transfer substrate and the adhesive layer at a position corresponding to the wiring conductor. Forming, and the step of introducing a conductive material into the through-hole, the step of forming a through-hole, which is excellent in mass productivity, and a printed wiring board with high utility value. It has the effect of being obtained.

A printed wiring board according to a twenty-second aspect of the present invention is a printed wiring board manufactured by the invention according to any one of the first to nineteenth aspects, wherein the printed wiring board is formed on a substrate and the substrate. And a wiring conductor that has been manufactured, and has an effect of obtaining a printed wiring board which is excellent in mass productivity and low in cost.

A printed wiring board according to a twenty-third aspect of the present invention is the printed wiring board manufactured according to the twentieth or twenty-first aspect, wherein the printed wiring board includes a substrate and a wiring conductor formed on the substrate. A through-hole penetrating the substrate, and a conductive material introduced into the through-hole; an effect of obtaining a printed wiring board excellent in mass productivity and low in cost; Having.

Hereinafter, an embodiment of the present invention will be described with reference to FIG.
This will be described with reference to FIG. (Embodiment 1) FIG. 1 is a perspective sectional view showing a master substrate for a method of manufacturing a printed wiring board according to Embodiment 1 of the present invention. In FIG. 1, a master substrate 1 forms a wiring conductor of a printed wiring board by a plating method, and has an action of peeling and transferring a wiring conductor on a transfer-receiving substrate. The master substrate 1 includes an insulating substrate 2 made of rigid glass or the like, a pattern electrode layer 3 for forming a wiring conductor of a predetermined shape on the insulating substrate 2 by plating, and a wiring conductor from the master substrate 1. And a release layer 4 for easy release.

FIGS. 2A to 2F show a method of manufacturing a printed wiring board according to the first embodiment of the present invention in which a printed wiring board is manufactured from the master substrate manufacturing step of forming such a master substrate.
This will be described with reference to the cross-sectional view of the main part of the present invention.

First, the master substrate shown in FIG. 2A is manufactured by a master substrate manufacturing process and a release layer forming process as described below. A 300-nm-thick Ni—Fe alloy film is formed on a rigid insulating substrate 2 made of a glass substrate by a sputtering method. Next, a positive photoresist is applied to a thickness of 2 μm by spin coating, exposed using a photomask, and developed with an aqueous solution of sodium carbonate to form a resist pattern corresponding to the pattern electrode layer 3. . Using this resist pattern as an etching mask, the Ni-Fe alloy film on the insulating substrate 2 is etched with an etching solution composed of an aqueous solution of nitric acid and acetic acid, and then the resist pattern is removed with an aqueous solution of sodium hydroxide. To form the pattern electrode layer 3. Thereby, master substrate 1 used in the method for manufacturing a printed wiring board according to Embodiment 1 of the present invention is manufactured.

Next, as shown in FIG. 2A, a release layer 4 having water repellency and conductivity is formed on the pattern electrode layer 3.
To form As a material of the release layer, a metal composite film made of nickel or the like containing graphite fluoride particles such as polytetrafluoroethylene formed in a plating method and formed by a vapor deposition method such as a sputtering method is used. A graphite thin film and a water-repellent thin film such as a fluorine-based coating agent such as a fluorine oil formed by a coating method or a dip coating method can be used. Here, in the case of a metal composite film containing graphite fluoride particles, it is necessary to form the graphite composite particles such that the graphite fluoride particles are uniformly dispersed in the metal film in a formed state. In the case of a graphite fluoride thin film or a fluorine-based coating agent, the conductivity of the film itself is low. However, when the film thickness at the time of film formation is 5 nm or more and 100 nm or less, water repellency and other electrodeposition are achieved. A thin film having a degree of conductivity that allows the resin to be electrodeposited is obtained. For example, according to an experiment conducted by the present inventors, a peeling layer was formed on a pattern electrode layer by a sputtering method to have a thickness of 5 nm, 15 nm, 30 nm, or 100 nm.
When a graphite fluoride thin film of each thickness of 10 nm is formed, the electrodeposited resin thin film can be electrodeposited with any thickness of the graphite fluoride thin film, and when the electrodeposited resin thin film is impregnated with moisture. In addition, it has been found that they have water repellency capable of sufficiently weakening the adhesion to the release layer. However, a graphite fluoride thin film having a thickness of 200 nm has no conductivity, and electrodeposition of an electrodeposited resin thin film is impossible. Electrodeposition was possible with a graphite fluoride thin film having a thickness of 3 nm. There was almost no water, and it was difficult to sufficiently weaken the adhesion of the electrodeposited resin thin film. That is, when the thickness of the release layer is smaller than 5 nm, the water repellency of the release layer is reduced, and the adhesion of the electrodeposited resin thin film to the release layer tends to be insufficiently reduced. In such a case, the resistance of the release layer becomes large and the electrodeposition resin thin film tends to be unable to be electrodeposited on the release layer. Further useful as a fluorine-based coating agent are fluorine oil, perfluorinated oil, and the like. When X and Y are hydrolyzable groups, silicon-based S is added to the terminal groups of these fluorine-based coating agents.
Those having iX3 and titanium-based TiY3 are preferable, and a hydrolysis reaction with a hydroxyl group or the like on the surface of the pattern electrode layer can be performed to make the adhesion stronger, and a release layer when the master substrate is repeatedly used. Can be improved in durability. In particular, when a water-repellent thin film composed of a perfluoropolyethylene having a silicon-based compound or a titanium-based compound as a terminal group is used for a release layer of a fluorine-based coating agent, these terminal groups may have an electrode layer or the like on a master plate. Since it has the property of easily adhering to the surface, it can be easily formed to a desired thickness by a dip coating method or the like, and since it is thin, a water-repellent thin film having conductivity in liquid is uniformly formed on the master plate. Can be.

Next, a step of forming an electrodeposited resin thin film and a wiring conductor on a master substrate in a method of manufacturing a printed wiring board according to Embodiment 1 of the present invention and a step of forming a wiring conductor are shown in FIG. This will be described with reference to b) and (c). FIG. 2B is a cross-sectional view of a main part of an electrodeposited resin thin film formed by electrodeposition on the master substrate, and FIG. 2C is a main part of a wiring conductor formed of a metal film plated on the master substrate. It is sectional drawing. 2B and 2C, reference numeral 5 denotes an electrodeposited resin thin film formed by an electrodeposition method, and 6 denotes a wiring conductor formed of a metal film formed by a plating method. The electrodeposited resin thin film 5 is applied to the surface of the pattern electrode 3 by using an electrodeposition method in which a voltage is applied to the metal counter electrode and the pattern electrode layer 3 on the master substrate 1 in an acrylic cationic electrodeposition resin bath. 100 nm thick on the formed release layer 4
Is obtained by an electrodeposition resin thin film forming step of forming an electrodeposition resin thin film 5 having the above-mentioned conductivity. Similarly, this wiring conductor 6
Has a thickness of 1 on the electrodeposited resin thin film 5 by copper electroplating.
It is obtained by a wiring conductor forming step of forming a wiring conductor 6 made of a copper plating film of 8 μm. The composition of the copper plating bath was as follows: 80 g / l of copper sulfate pentahydrate, 180 g / l of sulfuric acid, 2.5 mg / l of chloride ion, 2.5 ml / l of additive, and the remainder being water. Current density during plating is 3A
/ Dm2.

The thickness of the electrodeposited resin thin film 5 is preferably not less than 50 nm and not more than 500 nm for the following reasons. According to an experiment performed by the present inventors, when the thickness of the electrodeposited resin thin film 5 is extremely small and is about 30 nm, the electrodeposited resin thin film 5 has conductivity and the wiring conductor 6 can be formed by plating. However, the electrodeposited resin thin film 5 hardly water-hydrated in the water-containing step described later, and it was difficult to sufficiently weaken the adhesion of the electrodeposited resin thin film 5 to the release layer 4 in the subsequent release transfer step. . On the other hand, when the electrodeposited resin thin films 5 having the respective thicknesses of 50 nm, 100 nm, 300 nm, and 500 nm are formed on the pattern electrode layer, if the electrodeposited resin thin film 5 has these thicknesses, the wiring conductor is formed by plating. It is possible to have a water content capable of sufficiently weakening the adhesion of the electrodeposited resin thin film 5 to the release layer 4 in the subsequent release transfer step when the electrodeposited resin thin film 5 is impregnated with moisture. found. However, when the film thickness was increased to 600 nm, the resistance of the electrodeposited resin thin film 5 was large, the conductivity was lost, and the plating formation of the wiring conductor 6 tended to be difficult.

Next, in the method for manufacturing a printed wiring board according to the first embodiment of the present invention, a water impregnation step of impregnating the electrodeposited resin thin film 5 formed on the master substrate with moisture, the electrodeposited resin thin film 5 and the copper plating A peeling transfer step of peeling and transferring an electrodeposit formed by laminating the wiring conductors 6 made of a film onto a substrate to be transferred will be described with reference to cross-sectional views of the main parts of FIGS. 2 (d), (e) and (f). 2D, 2E and 2F, reference numeral 7 denotes water, 8 denotes a substrate to be transferred, and 10 denotes an adhesive layer. In the water-containing step, as shown in FIG.
By dipping the master substrate 1 on which the wiring conductors 6 are formed in layers, the electrodeposited resin thin film 5 is sufficiently impregnated with water. Here, the water-containing time is about 1 minute, but the water temperature of the water 7 to be water-containing is 30 or more and 8 for the reason described later.
The temperature must be 0 ° C. or lower, and particularly preferably around 50 ° C. As shown in FIGS. 2E and 2F, after the water-containing step, in the peeling transfer step, the electrodeposited resin thin film 5 whose adhesive force has been weakened by the water-containing step, and the wiring conductor 6 laminated thereon. Is deposited and transferred from the master substrate 1 onto the adhesive layer 10 provided on the transfer substrate 8. A flexible substrate such as a polyimide film or the like is used as the substrate to be transferred 8, and an epoxy-based adhesive or the like is applied as a bonding layer 10 to this by a roll coat. As shown in FIGS. 2E and 2F, the transferred substrate 8 and the master substrate 1
Is pressed in the direction shown in FIG. 2 (e), and then the master substrate 1 is peeled off, whereby the adhesive layer 10 provided on the transferred substrate 8 as shown in FIG. The electrodeposit formed of the electrodeposited resin thin film 5 and the wiring conductor 6 formed on the master substrate 1 is peeled and transferred. The release layer 4 is left on the master substrate 1 side.

According to the experiment conducted by the present inventors in the above-mentioned water-containing step, the temperature of the water 7 to be water-containing was 25 ° C.
In the case of (1), the water on the surface of the wiring conductor 6 cannot completely evaporate, and there is a tendency that sufficient adhesion between the adhesive layer 10 on the substrate 8 to be transferred and the wiring conductor 6 cannot be obtained in the peeling transfer process. Was done. On the other hand, the temperature of the water 7 is 30 ° C.
When the temperature is set to 40 ° C., 50 ° C., 60 ° C., and 70 ° C., moisture on the surface of the wiring conductor 6 is removed by evaporation, and
Sufficient adhesive strength is obtained with respect to the upper adhesive layer 10, and the adhesive force between the release layer 4 and the electrodeposited resin thin film 5 is also weakened by moisture impregnated inside the electrodeposited resin thin film 5, so that reproducibility is good. It was found that complete peeling transfer was possible. Especially water 7
When the temperature is around 50 ° C., there is a good relationship between the time for evaporating the water on the surface of the wiring conductor and the time for shifting from the water-containing step to the peeling and transferring step. It became clear that it was the most preferable. On the other hand, when the water temperature is 80 ° C., the water inside the electrodeposited resin thin film 5 evaporates and the adhesion between the release layer 4 and the electrodeposited resin thin film 5 cannot be sufficiently weakened. It was found that the transfer became difficult. That is, the temperature of the water 7 to be hydrated is 30
When the temperature is lower than 0 ° C., the water on the surface of the wiring conductor 6 is peeled off and transferred to the adhesive layer 10 of the substrate to be transferred 8 in a state where it cannot completely evaporate, and sufficient adhesion between the adhesive layer and the wiring conductor is obtained. When the temperature is higher than 80 ° C., on the contrary, the moisture inside the electrodeposited resin thin film 5 is easily evaporated, and the adhesion of the electrodeposited resin thin film 5 due to the water repellency of the release layer 4 is sufficiently weakened. Will tend to be unable to
Neither is preferred. The temperature of the water 7 is about 5
At 0 ° C., the water impregnated inside the electrodeposited resin thin film can sufficiently weaken the adhesion of the electrodeposited resin thin film to the release layer, and the time for evaporating the water on the wiring conductor surface is short, This is the most preferable in terms of workability because the waiting time when shifting from the water-containing step to the peeling transfer step is also reduced.

After the above-described peeling and transferring step, as shown in FIG.
By dissolving and removing the electrodeposited resin thin film 5 on the surface with an organic solvent such as alcohol, a high-precision and high-density printed wiring board can be obtained. In addition, the master substrate 1 after the separation transfer can be repeatedly used by returning to the above-described electrodeposited resin thin film forming step.

As described above, according to the first embodiment, the water-repellent thin film is used as the release layer 4, and the electrodeposited resin thin film 5 formed on the water-repellent thin film is impregnated with moisture. The adhesive force of the resin thin film 5 to the release layer 4 is significantly reduced, and the electrodeposited resin thin film 5 and the wiring conductors 6 formed thereon are formed on the adhesive layer 10 of the master substrate 1 and the transferred substrate 8.
It is possible to surely and completely remove and transfer the electrodeposit composed of. Here, since the peeling transfer is performed in a state where the adhesion of the electrodeposited resin thin film 5 to the peeling layer 4 is significantly reduced, the peeling transfer is performed without damaging the peeling layer 4 and the pattern electrode layer of the master substrate 1 at the same time. The wiring substrate 6 having the same shape can be formed with extremely high reproducibility using the master substrate 1 of the above, and the master substrate 1 can be used repeatedly.
The service life can be extended. Further, since the adhesion of the electrodeposited resin thin film 5 to the release layer 4 can be weakened,
Since the master substrate and the transfer-receiving substrate 8 are not forcibly peeled off at the time of peeling transfer, it is possible to prevent the shape of the wiring conductor 6 from being broken or damaged. When the number of times the master substrate 1 is used repeatedly increases, the release layer 4
Since the adhesion between the electrode layer 4 and the pattern electrode layer 4 may be reduced and the release layer 4 may be transferred in a state of being attached to the electrodeposited resin thin film 5 in the release transfer step, the release layer 4
Is preferably reproduced. However, in the case of the release layer 4 shown in the present embodiment, even if the release layer 4 adheres to the electrodeposited resin thin film 5 as described above, when the electrodeposited resin thin film 5 is removed with a solvent, the release layer 4 is also removed. Since it is removed, the wiring conductor 6 is not affected. In terms of durability, the release layer 4 is more chemically coated with the pattern electrode layer 3 by forming a fluorine-based coating agent than the metal composite film containing graphite fluoride particles and the graphite fluoride thin film. In the case of a fluorine-based coating agent, it can be formed on a master substrate by a dip coating method or the like very easily. Thereafter, the release layer 4 can be regenerated by coating every time. Further, in accordance with the series of steps as described above, the pattern electrode layer 3 for forming the wiring conductor 6 by plating is formed on the master substrate 1 by photolithography or the like.
Since it can be formed very densely and at a high density, it is possible to easily produce a high-definition and high-density wiring conductor with good mass productivity.

As described in the first embodiment, according to the present invention, the electrodeposited resin thin film is impregnated with moisture in the water-containing step, and the release layer is water-repellent. Adhesive force to the is significantly weakened,
An electrodeposit formed by laminating an electrodeposited resin thin film and a wiring conductor on the adhesive layer of the transfer-receiving substrate from the master substrate can be completely peeled and transferred reliably. Therefore, the printed wiring board obtained by the present invention has wiring conductors formed with high precision and high density, and is excellent in mass productivity.

Embodiment 2 Hereinafter, a method for manufacturing a printed wiring board according to Embodiment 2 of the present invention will be described. The second embodiment of the present invention is different from the first embodiment in the configuration of the master substrate 1. FIG. 3 is a perspective sectional view showing a master substrate for a method of manufacturing a printed wiring board according to Embodiment 2 of the present invention. In FIG. 3, the master substrate 1 forms a wiring conductor by plating in the same manner as in the first embodiment, and has a function of peeling and transferring the wiring conductor onto the transfer target substrate. The master substrate 1 includes an insulating substrate 2 made of rigid glass or the like, a wiring conductor forming electrode 12 for plating a wiring conductor laminated on the insulating substrate 2, and a wiring conductor forming electrode 12. An insulating masking layer 1 formed by laminating an insulating material on an electrode 12 and pattern-etching it into a negative shape of a predetermined wiring conductor.
1 and a release layer 4 for easily removing the wiring conductor from the master substrate 1.

FIGS. 4A to 4F show a method of manufacturing a printed wiring board according to the second embodiment of the present invention in which a printed wiring board is manufactured from the master substrate manufacturing step of forming such a master substrate.
This will be described with reference to the cross-sectional view of the main part of the present invention.

First, the master substrate forming step and the release layer forming step will be described with reference to the cross-sectional view of the main part of the master substrate shown in FIG. A wiring conductor forming electrode 12 for plating a wiring conductor on a rigid insulating substrate 2 made of a glass substrate is formed by forming a nickel film to a thickness of 300 nm by a sputtering method. A silicon oxide film having a thickness of 1 μm for forming the conductive masking layer 11 is formed by a sputtering method. Next, a positive photoresist is applied to a thickness of 2 μm by spin coating, exposed using a photomask, and developed with an aqueous solution of sodium carbonate to form a resist pattern corresponding to the negative shape of the wiring conductor. I do. Using this resist pattern as an etching mask, after etching the silicon oxide film on the surface with a fluorine-based etchant, the resist pattern is removed with an aqueous sodium hydroxide solution to form the insulating masking layer 11, and The wiring conductor forming electrode 12 is exposed. Thus, the master substrate 1 used in the method for manufacturing a printed wiring board is formed. Next, a release layer 4 having water repellency and conductivity is formed on the wiring conductor forming electrode 12. For release layer 4, a material equivalent to that of the first embodiment of the present invention is used.

Next, in the method for manufacturing a printed wiring board according to the second embodiment of the present invention, an electrodeposited resin thin film forming step for forming an electrodeposited resin thin film and a wiring conductor on a master substrate and a wiring conductor forming step are shown in FIG. Shown in b) and (c). FIG. 4B is a cross-sectional view of a main part of an electrodeposited resin thin film formed by electrodeposition on the master substrate, and FIG. 4C is a sectional view of a wiring conductor formed of a metal film plated on the electrodeposited resin thin film. It is principal part sectional drawing. In FIG. 4, reference numeral 5 denotes an electrodeposited resin thin film formed by an electrodeposition method, and 6 denotes a wiring conductor formed of a metal film formed by a plating method. As in the first embodiment,
After forming a conductive electrodeposited resin thin film 5 having a thickness of 200 nm on the release layer 4 formed on the surface of the wiring conductor forming electrode 12 on the master substrate 1 using an acrylic cation-type electrodeposited resin bath. Next, a wiring conductor 6 made of a copper plating film having a thickness of 18 μm is formed on the electrodeposited resin thin film 5 by copper electroplating.

Here, in the water-containing step shown in FIG. 4D, the master substrate 1 was formed on the master substrate 1 by immersing it in water 7 in the same manner as in the first embodiment of the present invention. The electrodeposited resin thin film 5 is sufficiently impregnated with moisture.

FIG. 11 is a diagram showing a peeling transfer step of peeling and transferring an electrodeposit formed by laminating a wiring conductor formed of an electrodeposited resin thin film and a copper plating film according to the second embodiment of the present invention to a substrate to be transferred. 4 (e) and 4 (f).
FIGS. 4 (e) and 4 (f) are cross-sectional views of main parts of a master substrate and a transfer-receiving substrate, showing a separation transfer step in the method for manufacturing a printed wiring board according to the second embodiment of the present invention. As in the first embodiment, the transferred substrate 8 and the master substrate 1 are
4 (f), the electrodeposited resin thin film 5 and the wiring conductor 6 formed on the master substrate 1 are separated from each other as shown in FIG. An object is peeled and transferred onto the adhesive layer 10 disposed on the substrate 8 to be transferred.

After the above-described separation transfer step, the transfer-receiving substrate 8
By dissolving and removing the electrodeposited resin thin film 5 on the surface of the wiring conductor 6 peeled and transferred on the surface with a solvent such as alcohol, FIG.
And a high-precision and high-density printed wiring board can be obtained. In addition, the master substrate after the separation transfer can be used repeatedly by returning to the above-mentioned electrodeposited resin thin film forming step.

In the second embodiment of the present invention, transfer to a flexible substrate is shown using a rigid master substrate. However, transfer to a rigid substrate using a flexible master substrate is also possible. Similar effects can be obtained. Similar effects can be obtained even with a thin metal foil as a flexible master substrate. Further, by forming the wiring conductor forming electrode of the master substrate from a material having corrosion resistance to the etching solution of the metal film to be the wiring conductor, when the wiring conductor remains on the master substrate, the wiring conductor is formed. The master substrate can be regenerated by etching away.

(Embodiment 3) FIG. 5 is a sectional view showing a main part of a printed wiring board according to Embodiment 3 of the present invention. In FIG. 5, 9 is a through hole, and 13 is a conductive material. Master substrate and release layer 4 formed thereon
The electrodeposited resin thin film 5 and the wiring conductor 6 are manufactured by a method equivalent to the first embodiment of the present invention or the second embodiment of the present invention. In the third embodiment of the present invention, the transferred substrate 8 or the transferred substrate 8 and the transferred substrate 8
In the adhesive layer 10 disposed above, the through holes 9 are formed in advance at portions corresponding to the wiring conductors. A process in which an electrodeposit formed of the electrodeposited resin thin film 5 and the wiring conductor 6 formed on the master substrate 1 is peeled and transferred onto an adhesive transfer substrate 8 or an adhesive disposed on the transfer substrate 8. The step of peeling and transferring onto the layer 10 is the same as in the first embodiment of the present invention or the second embodiment of the present invention. After the peeling and transferring step, a molten solder as the conductive material 13 was poured into the through hole 9 so that the conductive material 13 was electrically connected to the wiring conductor 6. As the conductive material 13, a form other than solder may be used, in which a lead made of copper is inserted and the end is connected to the wiring conductor 6. That is, when the through-hole 9 is formed in the transfer-receiving substrate 8 as in the present embodiment, the electrodes of the printed wiring board can be taken out through the through-hole 9 and very efficiently other electrodes can be obtained. Can be connected to electrical components. Further, since these printed wiring boards can be laminated, a multilayer printed wiring board excellent in mass productivity can be manufactured.

[0053]

According to the method of manufacturing a printed wiring board of the present invention, a water-repellent thin film is formed as a release layer, and an electrodeposition resin thin film and a metal plating film are laminated on the release layer. When the resin thin film is impregnated with water, the adhesiveness of the electrodeposited resin thin film to the release layer is significantly reduced because the release layer is water repellent, and the electrodeposition of the electrodeposited resin thin film onto the adhesive layer of the transferred substrate is performed. An electrodeposit formed by laminating the resin thin film and the wiring conductor can be completely and completely transferred. Accordingly, the present invention can form a wiring conductor of the same shape with extremely high reproducibility using the same master substrate without damaging the release layer or the pattern electrode layer of the master substrate during peel transfer. Can be used repeatedly to extend the service life, and even when an adhesive layer having a low adhesive strength is used for the transferred substrate, the shape of the wiring conductor can be prevented from being damaged, so that the wiring conductor can be formed with high reliability. The excellent effect that can be obtained is obtained.

According to the present invention, the pattern electrode layer forming the electrodeposited resin thin film and the wiring conductor can be formed very densely and with high density on the master substrate by photolithography or the like. By manufacturing and repeatedly using this, a low-cost, high-definition, high-density wiring conductor can be manufactured without using expensive equipment or complicated steps in the subsequent steps.

Therefore, the present invention can provide a method of manufacturing a printed wiring board which can mass-produce high-precision and high-density printed wiring boards at a low cost and with high reliability.

[Brief description of the drawings]

FIG. 1 is a perspective sectional view showing a master substrate for a method for manufacturing a printed wiring board according to Embodiment 1 of the present invention.

FIG. 2 is an essential part cross sectional view showing the method for manufacturing the printed wiring board in Embodiment 1 of the present invention.

FIG. 3 is a perspective sectional view showing a master substrate for a method of manufacturing a printed wiring board according to Embodiment 2 of the present invention.

FIG. 4 is an essential part cross sectional view showing the method for manufacturing the printed wiring board in Embodiment 2 of the present invention.

FIG. 5 is a sectional view of a principal part of a printed wiring board according to Embodiment 3 of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Master substrate 2 Substrate 3 Pattern electrode layer 4 Release layer 5 Electrodeposited resin thin film 6 Wiring conductor 7 Water 8 Transfer receiving substrate 9 Through hole 10 Adhesive layer 11 Insulating masking layer 12 Wiring conductor forming electrode 13 Conductive material

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Hidetoshi Matsumoto 1006 Kadoma Kadoma, Osaka Prefecture Matsushita Electric Industrial Co., Ltd.

Claims (23)

[Claims] A step of forming a pattern electrode layer having a predetermined shape on a substrate; a step of forming a release layer formed of a water-repellent thin film on the master substrate;
An electrodeposited resin thin film forming step of forming an electrodeposited resin thin film on the release layer, a wiring conductor forming step of forming a wiring conductor made of a metal film on the electrodeposited resin thin film, A method for manufacturing a printed wiring board, comprising: a water impregnating step of impregnating; and a peeling transfer step of peeling an electrodeposit formed by laminating the electrodeposited resin thin film and the wiring conductor from a master substrate and transferring the electrodeposit on a substrate to be transferred. . 2. The method according to claim 1, wherein the step of forming the master substrate includes the step of forming a conductive layer on an insulating substrate, and the step of forming a pattern electrode layer of a wiring conductor having a predetermined shape by etching the conductive layer. The method for manufacturing a printed wiring board according to claim 1, further comprising a layer forming step. 3. The method of manufacturing a master substrate, comprising: forming a conductive layer on an insulating substrate; forming an insulating layer on the conductive layer; and etching the insulating layer. 2. The method for manufacturing a printed wiring board according to claim 1, further comprising: an electrode layer forming step of forming a negative pattern electrode layer of the wiring conductor. 4. A method for forming a master substrate, comprising the steps of: forming a conductive layer for forming an insulating layer on a conductive substrate; and etching the insulating layer to form a negative pattern electrode layer of a wiring conductor having a predetermined shape. The method for manufacturing a printed wiring board according to claim 1, further comprising: an electrode layer forming step. 5. The method for manufacturing a printed wiring board according to claim 1, wherein said substrate has flexibility and said substrate to be transferred has rigidity. . 6. The method for manufacturing a printed wiring board according to claim 1, wherein said substrate to be transferred has flexibility, and said substrate has rigidity. . 7. The method according to claim 4, wherein the conductive substrate is a flexible metal foil. 8. The printed wiring board according to claim 1, wherein said electrode layer is made of a material having corrosion resistance to an etching solution for said wiring conductor. Manufacturing method. 9. The method according to claim 1, wherein said release layer forming step forms a release layer comprising a water-repellent thin film composed of a metal film containing graphite fluoride particles on said master substrate. Item 10. The method for manufacturing a printed wiring board according to any one of Items 8 to 18. 10. The method according to claim 1, wherein the release layer forming step includes forming a release layer made of a water-repellent thin film composed of a graphite fluoride thin film on the master substrate.
A method for manufacturing a printed wiring board according to claim 8. 11. The method according to claim 1, wherein in the release layer forming step, a release layer comprising a water-repellent thin film composed of a fluorine-based coating agent is formed on the master substrate.
A method for manufacturing a printed wiring board according to claim 8. 12. The release layer forming step includes forming a release layer made of a water-repellent thin film composed of perfluoropolyethylene having a silicon-based compound or a titanium-based compound as a terminal group on the master substrate. The method for manufacturing a printed wiring board according to any one of claims 1 to 8, wherein: 13. When the thickness of the release layer is 5 nm or more, 100
The diameter is not more than nm.
3. The method for manufacturing a printed wiring board according to any one of 2. 14. The electrodeposited resin thin film forming step of forming an electrodeposited resin thin film by an electrodeposition method.
A method for manufacturing a printed wiring board according to claim 13. 15. The method according to claim 1, wherein the thickness of the electrodeposited resin thin film is not less than 50 nm and not more than 500 nm. 16. The method for manufacturing a printed wiring board according to claim 1, wherein the wiring conductor forming step forms the wiring conductor by a plating method. 17. The method according to claim 17, wherein the water-containing step comprises:
The method for producing a printed wiring board according to any one of claims 1 to 16, wherein hot water of 80 ° C or less is impregnated as described above. 18. The method for manufacturing a printed wiring board according to claim 1, wherein the transfer surface of the transfer substrate has an adhesive property. 19. The transfer substrate according to claim 1, wherein an adhesive layer is provided on the transfer surface.
The method for producing a printed wiring board according to any one of the above. 20. The method according to claim 20, further comprising the steps of: forming a through hole in the substrate to be transferred at a position corresponding to the wiring conductor; and introducing a conductive material into the through hole. The method for producing a printed wiring board according to any one of claims 1 to 18. 21. A step of forming a through hole in the transfer substrate and the adhesive layer at a position corresponding to the wiring conductor;
20. The method according to claim 19, further comprising: introducing a conductive material into the through-hole. 22. A semiconductor device according to claim 1, further comprising a substrate and a wiring conductor formed on said substrate.
A printed wiring board manufactured by the method for manufacturing a printed wiring board according to any one of the above. 23. A semiconductor device comprising: a substrate; a wiring conductor formed on the substrate; a through hole penetrating the substrate; and a conductive material introduced into the through hole. 22. A printed wiring board manufactured by the method for manufacturing a printed wiring board according to claim 20, wherein the printed wiring board is electrically connected to a conductor.