JP4599997B2 - Manufacturing method of wiring board with built-in solid electrolytic capacitor - Google Patents

Description

The present invention relates to a method for manufacturing a wiring board incorporating a solid capacitor.

In order to have a configuration in which a high-capacitance capacitor is embedded in the substrate, it cannot be formed by one layer of the multilayer wiring board, and must be provided over two or more layers (see Patent Documents 1 to 3).
When a capacitor having a high capacity is embedded in the substrate as described above, two or more layers are required. Therefore, the area occupied by the substrate becomes large, and it becomes difficult to route the wiring layer.
Further, since two or more layers are required, it is difficult to embed a plurality of capacitors inside the substrate.

JP 2002-100870 A JP 2002-1000087 A JP 2002-246759 A

An object of the present invention is to provide a method of manufacturing a wiring board in which a high-capacity solid electrolytic capacitor is built in the wiring board.

The present invention as described in claim 1
(1) A step of forming a conductive polymer layer on one surface of an aluminum foil provided with an insulating film comprising an aluminum oxide layer on the surface;
(2) A step of partially forming a patterned insulating resin layer on the conductive polymer layer;
(3) forming a metal thin film layer on the aluminum foil surface, the conductive polymer resin layer, and the patterned insulating resin layer surface;
(4) forming an electrolytic copper plating layer on the metal thin film layer;
(5) The step of removing the electrolytic copper plating layer to leave a peripheral edge of the pattern shape on the insulating resin layer and forming a capacitor electrode;
(6) A step of laminating a printed wiring board on the insulating resin layer surface of the aluminum foil,
(7) forming a capacitor electrode on the other surface of the aluminum foil by photolithography, etching;
(8) forming an insulating layer on the capacitor electrode forming surface;
(9) A step of forming a conduction path of the capacitor electrode by laser processing on the insulating layer,
(10) A step of forming a plated metal layer on the conduction path;
(11) forming a wiring layer on the electrolytic copper plating layer;
This is a method for manufacturing a wiring board having a solid electrolytic capacitor built-in.

The present invention, as described in claim 2,
(1) A step of partially forming an insulating resin layer on one surface of an aluminum foil provided with an insulating coating composed of an aluminum oxide layer on the surface;
(2) A step of partially forming a conductive polymer resin layer on an aluminum foil on which the insulating resin layer is not formed,
(3) forming a metal thin film layer on the aluminum foil surface, the conductive polymer resin layer, and the patterned insulating resin layer surface;
(4) forming an electrolytic copper plating layer on the metal thin film layer;
(5) The step of removing the electrolytic copper plating layer to leave a peripheral edge of the pattern shape on the insulating resin layer and forming a capacitor electrode;
(6) A step of laminating a printed wiring board on the insulating resin layer surface of the aluminum foil,
(7) forming a capacitor electrode on the other surface of the aluminum foil by photolithography, etching;
(8) forming an insulating layer on the capacitor electrode forming surface;
(9) A step of forming a conduction path of the capacitor electrode by laser processing on the insulating layer,
(10) A step of forming a plated metal layer on the conduction path;
(11) forming a wiring layer on the electrolytic copper plating layer;
This is a method for manufacturing a wiring board having a solid electrolytic capacitor built-in.

The present invention, as described in claim 3,
(1) A step of forming a conductive polymer resin layer on one surface of an aluminum foil provided with an insulating film comprising an aluminum oxide layer on the surface;
(2) forming a capacitor electrode made of a patterned conductive paste on the conductive polymer resin layer;
(3) removing the conductive polymer resin layer not provided with the capacitor electrode;
(4) removing the insulating film of the aluminum foil;
(5) A step of forming a capacitor electrode made of a patterned conductive paste layer on the surface of the aluminum foil from which the insulating film has been removed, on which the capacitor electrode is provided,
(6) A step of laminating a printed wiring board on a surface of the aluminum foil from which the insulating film has been removed, on which the capacitor electrode is not formed,
(7) forming an insulating resin layer on the capacitor electrode forming surface;
(8) A step of forming a conduction path of the capacitor electrode by laser processing on the insulating layer,
(9) a step of forming a plated metal layer on the conductive path;
(10) forming a wiring layer on the electrolytic copper plating layer;
This is a method for manufacturing a wiring board having a solid electrolytic capacitor built-in.

According to the present invention, a capacitor is formed in advance on an aluminum foil, and this aluminum is integrated with a multilayer wiring substrate, thereby making it possible to manufacture a wiring substrate incorporating a high-capacity solid electrolytic capacitor.

The example of the manufacturing method of this invention is demonstrated based on FIG.
An insulating coating made of an aluminum oxide film is formed on the surface by chemical conversion treatment, and a conductive polymer resin is coated on one side of the roughened aluminum foil 1 (see FIG. 1A) by, for example, spin coating Then, the conductive polymer resin layer 2 is formed (see FIG. 1B).
Next, the insulating resin layer 3 is formed on the conductive polymer resin layer 2 at a position other than the capacitor electrode portion by, for example, screen printing (see FIG. 1C).
Next, a metal thin film 4 is formed on the entire surface of the aluminum foil 1 by sputtering (see FIG. 1D).
Then, a metal layer 5 is formed on the metal thin film 4 by electroplating (see FIG. 1 (e)).
On the surface of the metal layer 5 on the side where the conductive polymer resin layer 2 is provided, the metal layer 5 is patterned to form a capacitor electrode 6a (see FIG. 1 (f)).
After the capacitor electrode was formed, the aluminum foil 1 was laminated and integrated on the multilayer wiring board 7 by using, for example, an adhesive layer 8 made of a prepreg (see FIG. 1G).
Next, the surface of the metal layer 5 on the aluminum foil 1 side was patterned to form capacitor electrodes 4a and 1a (see FIG. 1 (h)).
After the capacitor electrode was formed, an insulating layer 9 was laminated. And in order to take out the electrode of a capacitor | condenser in the upper part of the insulating layer 9, the hole was formed in the insulating layer 9 using the carbon dioxide laser etc. (refer FIG.1 (i)).
Next, after forming a metal thin film made of a plating film on the insulating layer 9 (including the hole portion) by electroless plating, a metal layer 10 made of plating film was formed by electrolytic plating (FIG. 1 ( j)).
And the said metal layer 10 was patterned, the wiring layer 10a was formed, and the wiring board was manufactured (refer FIG.1 (l)).
Through the above steps, a wiring board incorporating a solid electrolytic capacitor could be manufactured.

Another manufacturing method of the present invention will be described with reference to FIG.
An insulating coating made of an aluminum oxide film is formed on the surface by chemical conversion treatment, and insulation is provided at a position other than the capacitor electrode portion on one side of a roughened aluminum foil 1 having a thickness of 40 μm (see FIG. 2A). A functional resin layer 3 was formed (see FIG. 2B).
Next, a conductive polymer resin was coated on the opening of the insulating resin layer 3 to form a conductive polymer resin layer 2 (see FIG. 2C).
Next, a metal thin film 4 was formed on the entire surface of the aluminum foil 1 by, eg, sputtering (see FIG. 2D).
Then, a metal layer 5 having a thickness of 12 μm was formed on the metal thin film 4 by, for example, an electrolytic plating method (see FIG. 2E).
The metal layer 5 on the side where the conductive polymer resin layer 2 was provided was patterned to form a capacitor electrode 6a (see FIG. 2 (f)).
After the capacitor electrode was formed, it was laminated and integrated with the multilayer wiring board 7 using the adhesive layer 8 (see FIG. 2G).
Next, the metal layer 5 on the aluminum foil 1 side was patterned to form capacitor electrodes 4a and 1a (see FIG. 2 (h)).
After the capacitor electrode was formed, an insulating layer 9 was laminated. And in order to take out the electrode of a capacitor | condenser on the upper part of the insulating layer 9, the hole was formed in the insulating layer 9 using the carbon dioxide laser etc. (refer FIG.2 (i)).
Next, after forming a metal thin film made of a plating film on the insulating layer 9 (including the hole portion) by electroless plating, a metal layer 10 made of plating film was formed by electrolytic plating (FIG. 2 ( j)).
Then, the metal layer 10 was patterned to form a wiring layer 10a (see FIG. 2 (l)).
Through the above steps, a wiring board incorporating a solid electrolytic capacitor could be manufactured.

FIG. 3 shows another example of the production method of the present invention.
First, as shown in FIG. 3A, the aluminum foil 1 is subjected to chemical conversion treatment, and an insulating film made of aluminum oxide is formed on the surface.
Next, as shown in FIG. 3B, a conductive polymer resin layer 2 is formed on one surface of the aluminum foil 1.
As shown in FIG. 3C, a conductive paste layer is partially provided on the conductive polymer resin layer 2 by screen printing to form a capacitor electrode 6. Then, after the capacitor electrode 6 is cured, the conductive polymer resin layer and the insulating film other than the capacitor electrode are removed by acid treatment.
Next, after drying, as shown in FIG. 3D, the capacitor electrode 20 is formed by screen-printing a conductive paste on the surface of the aluminum foil 1 from which the conductive polymer resin layer 2 has been removed.
Then, as shown in FIG. 3 (e), the solid electrolytic capacitor thus formed is laminated on the multilayer wiring board 7 via the adhesive layer 8. At this time, an insulating resin layer 30 is simultaneously formed on the capacitor electrodes 6 and 20.
Next, as shown in FIG. 3 (f), in order to connect the capacitor electrode to the circuit, the insulating resin layer 30 is subjected to drilling in a portion where the capacitor electrode is provided by laser processing, and the drilling insulating resin 30a. Form.
As shown in FIG. 3G, a metal thin film is formed on the perforated insulating resin 30a by electroless plating, and then the metal layer 10 is formed by electrolytic plating.
And as shown in FIG.3 (h), the said metal layer 10 forms the wiring layer 10a by the photolithographic process and an etching, and the wiring board incorporating a solid electrolytic capacitor is manufactured.

Example 1
An embodiment of the present invention will be described with reference to FIG.
An insulating coating composed of an aluminum oxide film is formed on the surface by chemical conversion treatment, and spin coating is performed on one side of a roughened aluminum foil 1 having a thickness of 40 μm (see FIG. 1 (a)) at 1000 rpm for 30 seconds. The conductive polymer resin was coated and dried in an oven at 80 ° C. to form a conductive polymer resin layer 2 having a thickness of 1 μm (see FIG. 1B).
Next, a solder resist coated on the surface of the printed wiring board is printed on the conductive polymer resin layer 2 at a position other than the capacitor electrode portion by screen printing, and dried at 140 ° C. An insulating resin layer 3 having a thickness of 10 μm was formed (see FIG. 1C).
Next, a metal thin film 4 having a thickness of 0.3 μm was formed on the entire surface of the aluminum foil 1 by sputtering copper (see FIG. 1D).
Then, copper was plated on the metal thin film 4 by an electrolytic plating method to form a metal layer 5 having a thickness of 12 μm (see FIG. 1 (e)).
After laminating a dry resist film (RY3315, thickness 15 μm, manufactured by Hitachi Chemical Co., Ltd.) on the surface of the metal layer 5 on the side where the conductive polymer resin layer 2 is provided, the mask pattern is exposed at an exposure amount of 40 mJ / cm 2. The metal layer 5 was patterned with an etching solution made of ferric chloride solution to form a capacitor electrode 6a (see FIG. 1 (f)).
After forming the capacitor electrode, the aluminum foil 1 from which the remaining dry resist film was removed using a 5% sodium hydroxide solution was placed on a multilayer wiring board 7 with a prepreg having a thickness of 80 μm (AS manufactured by Hitachi Chemical Co., Ltd.). The adhesive layer 8 made of -5000GP) was laminated and integrated by vacuum pressing (see FIG. 1 (g)).
Next, after laminating a dry resist film (RY3315, thickness 15 μm, manufactured by Hitachi Chemical Co., Ltd.) on the surface of the metal layer 5 on the aluminum foil 1 side, the mask pattern is exposed at an exposure amount of 40 mJ / cm 2, and then a 1% sodium carbonate solution Then, the metal layer 5 was patterned with an etching solution made of ferric chloride solution to form capacitor electrodes 4a and 1a (see FIG. 1 (h)).
After the capacitor electrode was formed, the remaining dry resist film was removed using a 5% strength sodium hydroxide solution, and again on the capacitor electrodes 4a and 1a, a prepreg having a thickness of 80 μm (AS-5000GP manufactured by Hitachi Chemical Co., Ltd.). The insulating layer 9 made of And in order to take out the electrode of a capacitor | condenser on the upper part of the insulating layer 9, the hole of 80 micrometers in diameter was formed in the insulating layer 9 using the carbon dioxide laser (refer FIG.1 (i)).
Next, after forming a 1 μm metal thin film made of a copper plating film on the insulating layer 9 (including the hole portion) by electroless copper plating, the film is made of a 12 μm thick copper plating film by electrolytic copper plating. A metal layer 10 was formed (see FIG. 1 (j)).
Then, after laminating a dry resist film (RY3315 thickness 15 μm, manufactured by Hitachi Chemical Co., Ltd.) on the surface of the metal layer 10, the mask pattern is exposed with an exposure amount of 40 mJ / cm 2, and then developed with a 1% concentration sodium carbonate solution, Further, the metal layer 10 was patterned with an etching solution made of ferric chloride solution to form a wiring layer 10a. Subsequently, after the wiring layer was formed, the remaining dry resist film was removed using a 5% strength sodium hydroxide solution to manufacture a wiring board (see FIG. 1 (l)).
Through the above steps, a wiring board incorporating a solid electrolytic capacitor could be manufactured.

(Example 2)
An embodiment of the present invention will be described with reference to FIG.
A solder that forms an insulating film made of an aluminum oxide film on the surface by chemical conversion treatment, and is coated on the surface of the printed wiring board on one side of the roughened aluminum foil 1 (see FIG. 2A) having a thickness of 40 μm. The resist was printed at a position other than the capacitor electrode portion by screen printing and dried at 140 ° C. to form an insulating resin layer 3 having a thickness of 10 μm (see FIG. 2B).
Next, the conductive polymer resin layer 2 having a thickness of 1 μm is formed by coating the opening of the insulating resin layer 3 with a conductive polymer resin by screen printing and drying in an oven at 80 ° C. (See FIG. 2 (c)).
Next, a thin metal film 4 having a thickness of 0.3 μm was formed on the entire surface of the aluminum foil 1 by sputtering copper (see FIG. 2D).
Then, copper was plated on the metal thin film 4 by an electrolytic plating method to form a metal layer 5 having a thickness of 12 μm (see FIG. 2E).
After laminating a dry resist film (RY3315, thickness 15 μm, manufactured by Hitachi Chemical Co., Ltd.) on the surface of the metal layer 5 on the side where the conductive polymer resin layer 2 is provided, the mask pattern is exposed at an exposure amount of 40 mJ / cm 2. Development processing was performed with a sodium carbonate solution having a concentration of%, and the metal layer 5 was patterned with an etching solution made of a ferric chloride solution to form a capacitor electrode 6a (see FIG. 2 (f)).
After forming the capacitor electrode, the aluminum foil 1 from which the remaining dry resist film was removed using a 5% sodium hydroxide solution was placed on a multilayer wiring board 7 with a prepreg having a thickness of 80 μm (AS manufactured by Hitachi Chemical Co., Ltd.). The adhesive layer 8 made of -5000GP) was laminated and integrated by vacuum pressing (see FIG. 2 (g)).
Next, after laminating a dry resist film (RY3315, thickness 15 μm, manufactured by Hitachi Chemical Co., Ltd.) on the surface of the metal layer 5 on the aluminum foil 1 side, the mask pattern is exposed at an exposure amount of 40 mJ / cm 2, and then a 1% sodium carbonate solution Then, the metal layer 5 was patterned with an etching solution made of ferric chloride to form capacitor electrodes 4a and 1a (see FIG. 2 (h)).
After the capacitor electrode was formed, the remaining dry resist film was removed using a 5% strength sodium hydroxide solution, and again on the capacitor electrodes 4a and 1a, a prepreg having a thickness of 80 μm (AS-5000GP manufactured by Hitachi Chemical Co., Ltd.). The insulating layer 9 made of And in order to take out the electrode of a capacitor | condenser on the upper part of the insulating layer 9, the hole of 80 micrometers in diameter was formed in the insulating layer 9 using the carbon dioxide laser (refer FIG.2 (i)).
Next, after forming a 1 μm metal thin film made of a copper plating film on the insulating layer 9 (including the hole portion) by electroless copper plating, the film is made of a 12 μm thick copper plating film by electrolytic copper plating. A metal layer 10 was formed (see FIG. 2 (j)).
Then, after laminating a dry resist film (RY3315 thickness 15 μm, manufactured by Hitachi Chemical Co., Ltd.) on the surface of the metal layer 10, the mask pattern is exposed with an exposure amount of 40 mJ / cm 2, and then developed with a 1% concentration sodium carbonate solution, Further, the metal layer 10 was patterned with an etching solution made of ferric chloride solution to form a wiring layer 10a. Subsequently, after the wiring layer was formed, the remaining dry resist film was removed using a 5% strength sodium hydroxide solution to manufacture a wiring board (see FIG. 2 (l)).
Through the above steps, a wiring board incorporating a solid electrolytic capacitor could be manufactured.

(Example 3)
An embodiment of the present invention will be described with reference to FIG.
An insulating film made of an aluminum oxide film is formed on the surface by chemical conversion treatment, and spin coating is performed on one surface of a roughened aluminum foil 1 having a thickness of 40 μm (see FIG. 3A) at 1000 rpm for 30 seconds. The conductive polymer resin was coated, and dried in an oven at 80 ° C. to form a conductive polymer resin layer 2 having a thickness of 1 μm.
Next, a capacitor electrode 6 was formed on the conductive polymer resin layer 2 by screen printing using a conductive paste made of copper paste and silver paste (see FIG. 3B).
Here, the capacitor electrode 6 was formed by providing a conductive paste with a thickness of 15 to 20 μm, followed by preliminary drying at 80 ° C. for 30 minutes and baking at 150 ° C. for 1 hour.
Next, the conductive polymer resin layer 2 and the insulating film other than the electrode part were removed by dipping in a 10% hydrochloric acid solution (see FIG. 3C).
And the capacitor electrode 20 was formed between the said capacitor electrodes by the said screen paste printing method (refer FIG.3 (d)).
The aluminum foil 1 was laminated and integrated on the multilayer wiring board 7 by a vacuum press using an adhesive layer 8 made of a prepreg (AS-5000GP manufactured by Hitachi Chemical Co., Ltd.) having a thickness of 80 μm. Further, an insulating layer 30 made of a prepreg (AS-5000GP manufactured by Hitachi Chemical Co., Ltd.) having a thickness of 80 μm was laminated on the capacitor electrodes 6a and 20 (see FIG. 3 (e)).
Next, in order to take out the electrode of the capacitor above the insulating layer 20, an insulating layer 20a in which a hole having a diameter of 80 μm was formed in the insulating layer 20 using a carbon dioxide gas laser was formed (see FIG. 3F).
Next, a 1 μm metal thin film made of a copper plating film is formed on the insulating layer 20a (including the hole portion) by an electroless copper plating method, and then a copper plating film having a thickness of 12 μm is formed by an electrolytic copper plating method. A metal layer 10 was formed (see FIG. 3G).
Then, after laminating a dry resist film (RY3215 thickness 15 μm, manufactured by Hitachi Chemical Co., Ltd.) on the surface of the metal layer 10, the mask pattern is exposed at an exposure amount of 40 mJ / cm 2 and developed with a 1% concentration sodium carbonate solution. Further, the metal layer 10 was patterned with an etching solution made of ferric chloride solution to form a wiring layer 10a. Subsequently, after the wiring layer was formed, the remaining dry resist film was removed using a 5% strength sodium hydroxide solution to manufacture a wiring board (see FIG. 3H).
Through the above steps, a wiring board incorporating a solid electrolytic capacitor could be manufactured.

Explanatory drawing which shows an example of the manufacturing method of the wiring board with a built-in electrolytic capacitor of this invention. Explanatory drawing which shows the other example of the manufacturing method of the electrolytic capacitor built-in wiring board of this invention. Explanatory drawing which shows the other example of the manufacturing method of the electrolytic capacitor built-in wiring board of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ......... Aluminum foil 2 ......... Conductive polymer resin layer 2a ......... Patterning conductive polymer resin layer 3, 9, 30 ......... Insulating resin layer 4 ......... Metal thin film 5, 10 ... ... Metal layers 6, 6a, 20 ......... Capacitor electrode 7 ......... Multilayer wiring substrate 8 ...... Adhesive layer 10a ......... Wiring layer 30a ......... Perforated insulating layer

Claims (3)

(1) A step of forming a conductive polymer layer on one surface of an aluminum foil provided with an insulating film comprising an aluminum oxide layer on the surface;
(2) A step of partially forming a patterned insulating resin layer on the conductive polymer layer;
(3) forming a metal thin film layer on the aluminum foil surface, the conductive polymer resin layer, and the patterned insulating resin layer surface;
(4) forming an electrolytic copper plating layer on the metal thin film layer;
(5) The step of removing the electrolytic copper plating layer to leave a peripheral edge of the pattern shape on the insulating resin layer and forming a capacitor electrode;
(6) A step of laminating a printed wiring board on the insulating resin layer surface of the aluminum foil,
(7) forming a capacitor electrode on the other surface of the aluminum foil by photolithography, etching;
(8) forming an insulating layer on the capacitor electrode forming surface;
(9) A step of forming a conduction path of the capacitor electrode by laser processing on the insulating layer,
(10) A step of forming a plated metal layer on the conduction path;
(11) forming a wiring layer on the electrolytic copper plating layer;
A method of manufacturing a wiring board incorporating a solid electrolytic capacitor by the above process. (1) A step of partially forming an insulating resin layer on one surface of an aluminum foil provided with an insulating coating composed of an aluminum oxide layer on the surface;
(2) A step of partially forming a conductive polymer resin layer on an aluminum foil on which the insulating resin layer is not formed,
(3) forming a metal thin film layer on the aluminum foil surface, the conductive polymer resin layer, and the patterned insulating resin layer surface;
(4) forming an electrolytic copper plating layer on the metal thin film layer;
(5) The step of removing the electrolytic copper plating layer to leave a peripheral edge of the pattern shape on the insulating resin layer and forming a capacitor electrode;
(6) A step of laminating a printed wiring board on the insulating resin layer surface of the aluminum foil,
(7) forming a capacitor electrode on the other surface of the aluminum foil by photolithography, etching;
(8) forming an insulating layer on the capacitor electrode forming surface;
(9) A step of forming a conduction path of the capacitor electrode by laser processing on the insulating layer,
(10) A step of forming a plated metal layer on the conduction path;
(11) forming a wiring layer on the electrolytic copper plating layer;
A method of manufacturing a wiring board incorporating a solid electrolytic capacitor by the above process. (1) A step of forming a conductive polymer resin layer on one surface of an aluminum foil provided with an insulating film comprising an aluminum oxide layer on the surface;
(2) forming a capacitor electrode made of a patterned conductive paste on the conductive polymer resin layer;
(3) removing the conductive polymer resin layer not provided with the capacitor electrode;
(4) removing the insulating film of the aluminum foil;
(5) A step of forming a capacitor electrode made of a patterned conductive paste layer on the surface of the aluminum foil from which the insulating film has been removed, on which the capacitor electrode is provided,
(6) A step of laminating a printed wiring board on a surface of the aluminum foil from which the insulating film has been removed, on which the capacitor electrode is not formed,
(7) forming an insulating resin layer on the capacitor electrode forming surface;
(8) A step of forming a conduction path of the capacitor electrode by laser processing on the insulating layer,
(9) a step of forming a plated metal layer on the conductive path;
(10) forming a wiring layer on the electrolytic copper plating layer;
A method of manufacturing a wiring board incorporating a solid electrolytic capacitor by the above process.

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