JPH0645735A - Manufacturing method and device of printed-wiring board - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide a method for manufacturing a printed wiring board used in various electronic devices, which not only significantly improves productivity and yield but also improves reliability of the electronic device. With the goal. A step of exposing a photo-developing solder resist ink 12a, a step of heating a printed wiring board 11, and a photo-developing solder resist ink 12a using a manufacturing apparatus equipped with an exposure section and a heating section. By providing the step of developing the
It is possible to accelerate the photo-crosslinking reaction in the exposed part, and it is possible to reduce the exposure time with a low exposure amount and a short exposure time and the standing time after the exposure.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for manufacturing a printed wiring board used in various electronic devices.

[0002]

2. Description of the Related Art In recent years, printed wiring boards, which are widely used in various electronic devices and the like, have been remarkably increased in wiring density and surface mounting of electronic parts due to miniaturization and multifunction of electronic devices. Conductor patterns formed on the board and lands on which electronic components are mounted are becoming increasingly narrower in pitch, thinner and smaller, preventing solder from adhering to unnecessary parts, protecting conductor patterns against oxidation, and maintaining insulation. High resolution and high positional accuracy are required for solder resists and roadmaps that are formed on printed wiring boards for the purpose of improving solderability. It is replacing the law.

A conventional printed wiring board will be described below. FIG. 7 shows a conventional printed wiring board manufacturing apparatus, and FIGS. 8A to 8D and 9A and 9B show a conventional printed wiring board manufacturing process. In the figure, 1 is a printed wiring board, 1a is an insulating substrate, 1b is a conductor pattern, 2a is a solder resist ink for photographic development, 2b is a formed solder resist, 3 is a solder resist forming mask film, 4 is ultraviolet rays, and 5a. Is a solder resist ink for photographic development peeled off from the printed wiring board 1, 5b is a solder resist non-adhered portion after development, and 5c is a solder resist residue after development. 6 is a dry part to the touch, 7
Is an exposure section, and 8 is a development section.

The formation of the solder resist of the printed wiring board constructed as above will be described below.

First, an etching resist is formed on a copper clad laminate (not shown) cut into a predetermined size by a screen printing method, a photographic method or the like, and then etching is performed using a solution of cupric chloride or the like. Then, the conductor pattern 1b is formed and the etching resist is peeled off. Next, FIG. 8 (a)
As shown in FIG. 7, the photo-developing solder resist ink 2a is applied to the printed wiring board 1 on which the conductor pattern 1b is formed on the insulating substrate 1a, and as shown in FIG. After drying, it is left to cool for about 5 to 10 minutes.

Then, as shown in FIG. 8B, the solder resist forming mask film 3 is brought into vacuum contact with the surface of the photographic developing solder resist ink 2a which has been dried by touch with the finger and left to cool, and as shown in FIG. At 500-800mJ
After being exposed to ultraviolet rays 4 with a light amount of / cm ² , the vacuum is released as shown in FIG. 8 (c), the photographic developing solder resist ink 2 a and the solder resist forming mask film 3 are peeled off, and then for 10 to 20 minutes. 7 and 8 after leaving
As shown in (d), the developing unit 7b develops and removes the unexposed portion with a predetermined developing solution to form a solder resist 2b.

Then, the solder resist 2a is formed on the printed wiring board 1 by re-hardening with hot air or the like.

[0008]

However, in the above-mentioned conventional structure, although the formed solder resist 2b has a high resolution, the application of the solder resist 2a for photographic development, touch-drying, leaving-cooling, exposure, development is carried out. There are many re-curing and manufacturing processes. Among the manufacturing processes, the exposure process is for aligning the mask film 3 for solder resist formation with the printed wiring board 1, vacuum adhesion, UV irradiation 4, vacuum release, for solder resist formation. This is complicated because the mask film 3 is peeled off and left undeveloped until development, which requires a lot of work time and hinders the productivity of forming the solder resist 2b.

When the vacuum is released and the solder resist forming mask film 3 is peeled from the printed wiring board 1,
Although the mask film 3 for forming a solder resist has a slight tackiness even if it is dried by touch and left to cool, the solder resist ink 2a surface for photographic development has increased tackiness due to the heat of an exposure light source such as a metal halide or an ultra-high pressure mercury lamp. 8 (c), the photographic developing solder resist ink 2a was peeled off from the printed wiring board 1 and was peeled off to the solder resist forming mask film 3 as shown in FIG. 8 (c). Printed wiring board 1 to which 5a is attached and exposed after the attachment
8D, the exposed portion of the photographic developing solder resist ink 5a that has been peeled off from the solder resist forming mask film 3 as shown in FIG.
As shown in FIG. 3, there is a risk that the solder resist unattached portion 5b is developed and removed in the developing step.

Further, as shown in FIG. 9A, when the peeled photographic developing solder resist ink 5a adheres to the solder resist forming mask film 3, the photographic developing type solder resist ink 2a is dried by touch. 9A and a solder resist forming mask film 3 have an adhesion defective portion having a gap between them, and ultraviolet light 4 penetrates through the gap of the adhesion defective portion to expose the photographic developing solder resist ink 2a to light. As shown in (), after development, the solder resist residue 5c is generated in an unnecessary portion. Then, this deteriorates the printed wiring board manufacturing yield, and further hinders the solderability at the time of soldering in electronic device manufacturing,
It has a problem that it may affect the reliability of electronic devices.

The present invention solves the above-mentioned conventional problems, and improves the productivity of the solder resist forming process by the photographic development method, significantly improves the yield of the manufacturing process, and improves the reliability of electronic equipment. An object of the present invention is to provide a wiring board manufacturing method and a manufacturing apparatus therefor.

[0012]

In order to achieve this object, a method of manufacturing a printed wiring board according to the present invention comprises a step of applying a solder resist ink for photographic development to a printed wiring board and drying by touch, and the above-mentioned photographic development. There is a step of exposing the solder resist ink for use in a desired shape, a step of heating the printed wiring board immediately after the exposure, and a step of developing the solder resist ink for photographic development thereafter.

The method for manufacturing a printed wiring board according to the present invention comprises the steps of applying a solder resist ink for photographic development to a printed wiring board and drying it by touching, cooling the printed wiring board, and then performing the photographic development. The method includes a step of exposing the solder resist to a desired shape and a step of developing a solder resist ink for photographic development thereafter.

Further, the method for producing a printed wiring board according to the present invention comprises the steps of applying a photographic developing solder resist ink to the printed wiring board, drying by touching with a finger, cooling the printed wiring board, and then the photographic developing solder. The method includes the steps of exposing the resist to a desired shape, heating the printed wiring board immediately after the exposure, and then developing the solder resist ink for photographic development.

[0015]

The photopolymerization reaction during exposure is roughly divided into the following four reactions. First, the photopolymerization initiator is cleaved into radicals by ultraviolet light, and the monomer is also cleaved. Next, a growth reaction / chain transfer reaction occurs, and finally there is a termination reaction. With the above configuration, a growth reaction in the photopolymerization reaction of the exposed portion of the solder resist ink for photographic development by irradiating infrared rays / near infrared rays immediately after exposure or by heating with hot air,
The chain transfer reaction is promoted and terminated by the termination reaction. As a result, it is possible to reduce the exposure amount with a low exposure amount, that is, a short exposure time and the leaving time after the exposure.

Further, since the printed wiring board is exposed to ultraviolet rays after being cooled, the tackiness of the solder resist ink for photographic development dried by touch is lowered, and at the same time, the temperature rise of the printed wiring board due to the irradiation of ultraviolet rays during exposure is suppressed. This makes it possible to prevent the solder resist ink for photographic development and the mask film for solder resist formation on the printed wiring board from adhering when the vacuum is released after exposure.

Furthermore, by cooling the printed wiring board and heating it after exposure, the tackiness of the solder resist ink for photographic development is reduced, and the temperature rise of the printed wiring board due to ultraviolet irradiation during exposure is suppressed and the heating is performed immediately after exposure. Photo-development solder resist ink The photo-polymerization reaction in the exposed area can be accelerated, and the adhesion of the photo-development solder resist ink on the printed wiring board to the solder resist forming mask film can be prevented when releasing the vacuum after exposure. At the same time, the exposure with a low exposure amount and a short exposure time and the leaving time after the exposure can be reduced.

[0018]

(Embodiment 1) An embodiment of the present invention will be described below with reference to the drawings. 1 (a)-(d)
Shows a manufacturing process of the printed wiring board in the first embodiment of the present invention, and FIG. 2 is a conceptual diagram of a printed wiring board manufacturing apparatus in the first embodiment of the present invention. 1 (a)-
In (d) and FIG. 2, 11 is a printed wiring board, 1
1a is an insulating substrate, 11b is a conductor pattern, 12a is a solder resist ink for photographic development, 12b is a solder resist formed, 13 is a mask film for forming a solder resist, 14 is ultraviolet rays, 15 is infrared rays, and 16 is a touch-drying portion. ,
Reference numeral 17 is an exposure unit, 18 is a heating unit, and 19 is a development unit.

The operation of the method and apparatus for manufacturing the printed wiring board having the above structure will be described with reference to FIGS. 1 and 2.

First, as shown in FIG. 1A, a conductor pattern 11b is formed on an insulating substrate 11a by using a method similar to the conventional method.
The photographic developing solder resist ink 12a is applied onto the printed wiring board 11 on which the film has been formed by means of screen printing, a roll coater, a curtain coater or the like, and a temperature of 60 to 60 80 ℃, time 15
Touch dry and leave to cool for about 30 minutes. Next, the solder resist forming mask film 14 is aligned with the printed wiring board 11 as shown in FIG.
After vacuum contact with an exposure unit 17 as shown in FIG. 2, ultraviolet exposure is performed with a light amount of about 200 to 250 mJ / cm ² .

Next, as shown in FIG. 1 (c), the mask film 13 for forming the solder resist and the printed wiring board 11 are evacuated and peeled off, and immediately the printed wiring board 11 is heated by the heating section 18 shown in FIG. The sample is irradiated with near infrared rays or infrared rays 15 of 500 to 2000 nm for 10 to 60 seconds and heated.
Then, as shown in FIG. 1D and FIG. Develop the unexposed areas of the solder resist ink for photographic development with a developer containing trichloroethane as the main component.
Remove.

After that, a temperature of 130 to 1 is set in a hot air circulation tank or the like.
The final curing is performed under the conditions of 60 ° C. and time of about 30 to 60 minutes to stabilize the adhesion between the insulating substrate 11a, the conductor pattern 11b and the solder resist 12b.

As described above, according to this embodiment, the printed wiring board is coated with the solder resist ink for photographic development by using the printed wiring board manufacturing apparatus provided with the exposing section, the heating section and the developing section.・ By touch-drying step, exposing the photographic developing solder resist ink to a desired shape, heating the printed wiring board immediately after exposure, and developing the photographic developing solder resist ink The amount of exposure light, that is, the exposure time can be halved, and the infrared irradiation time after exposure will be significantly reduced compared to the conventional standing time until development after exposure, so productivity in the entire exposure process will be more than doubled. can do.

(Second Embodiment) A second embodiment of the present invention will be described below with reference to the drawings. Fig.3 (a)-
FIG. 4E is a sectional view showing a manufacturing process of the printed wiring board in the second embodiment of the present invention, and FIG. 4 is a conceptual diagram of a printed wiring board manufacturing apparatus in the second embodiment of the present invention. 3 and 4, 11 is a printed wiring board,
11a is an insulating substrate, 11b is a conductor pattern, 12a is a solder resist ink for photographic development, 12b is a solder resist that has been formed, 13 is a solder resist forming mask film, 14 is ultraviolet rays, 16 is a touch-free portion, and 17 is exposure. Reference numeral 19 designates a developing portion, which has the same construction as that shown in FIGS. 1 and 2 is different from the heating unit 18 in that a cooling unit 20 is provided immediately before the exposure unit 17.

The operation of the method and apparatus for manufacturing the printed wiring board configured as described above will be described with reference to FIGS. 3 and 4.

First, as shown in FIG. 3A, a conductor pattern 11b is formed on the insulating substrate 11a by using the same method as the conventional method.
The solder resist ink 12a for photographic development is applied onto the printed wiring board 11 on which the film has been formed by means of screen printing, a roll coater, a curtain coater, etc. ~ 80 ° C, time 15
Touch dry for about 30 minutes, and then
As shown in (b) and FIG. 4, the printed wiring board 11 is cooled by the cooling unit 20 so that the surface temperature becomes 15 to 18 ° C., and immediately, as shown in FIG. 3 (c), the solder resist forming mask film 13 is formed. After being aligned with the printed wiring board 11, they are vacuum-contacted in an exposure unit 17 as shown in FIG. 3 and exposed to ultraviolet light with a light amount of about 500 to 800 mJ / cm ² . Then, as shown in FIG. 3D and FIG.
9 at 1.1.1. The unexposed portion of the photographic developing solder resist 12a is developed and removed with a developing solution containing trichloroethane as a main component.

Thereafter, a temperature of 130 to 1 is set in a hot air circulation tank or the like.
Final curing is performed under the conditions of 60 ° C. and time of about 30 to 60 minutes to stabilize the adhesion to the insulating substrate 11a, the conductor pattern 11b and the solder resist 12b.

As described above, according to this embodiment, the printed wiring board is coated with the solder resist ink for photographic development by using the printed wiring board manufacturing apparatus having the cooling unit, the exposing unit and the developing unit. The printed wiring board before exposure is composed of a step of drying by touch, a step of cooling the printed wiring board, a step of exposing the photographic developing solder resist to a desired shape, and a step of developing the photographic developing solder resist ink. Cooling is possible without leaving it to cool, the tackiness of the solder resist ink for photo development is reduced, and the peeling property between the solder resist ink for photo development and the mask film for solder resist formation is released when the vacuum is released after exposure to ultraviolet light. It is possible to improve the solder resist ink for photographic development on the mask film for forming the solder resist even after continuous exposure of 1000 sheets. Adhering never completely occur,
No problems such as unexposed solder resist due to the adhesion of the photographic developer solder resist ink to the solder resist forming mask film were observed.

(Embodiment 3) A third embodiment of the present invention will be described below with reference to the drawings. FIG. 5 (e) is a sectional view showing the manufacturing process of the printed wiring board in the third embodiment of the present invention, and FIG. 6 is a conceptual view of the same manufacturing apparatus for the printed wiring board. 5 and 6, 11 is a printed wiring board, 11a is an insulating substrate, 11b is a conductor pattern, 12a is a solder resist ink for photographic development, and 12b.
Is a formed solder resist, 13 is a mask film for forming a solder resist, 14 is ultraviolet rays, 15 is infrared rays, 1
6 is a touch-drying section, 17 is an exposing section, 19 is a developing section, and 18 is a heating section. The above is the same as the configuration of FIGS. 1 and 2. 1 and 2 is different in that a cooling unit 20 is provided immediately before the exposure unit 17.

The operation of the method for manufacturing the printed wiring board having the above structure will be described below with reference to FIGS.

First, as shown in FIG. 5A, a conductive pattern 11b is formed on the insulating substrate 11a by using the same method as the conventional method.
The photographic developing solder resist ink 12a is applied on the printed wiring board 11 on which the film has been formed by means of screen printing, a roll coater, a curtain coater or the like, and a temperature of 60 to 60 80 ℃, time 15
Touch dry for about 30 minutes and then, as shown in FIG.
As shown in FIG. 6B and FIG. 6, the printed wiring board 11 is cooled in the cooling unit 20 so that the surface temperature becomes 15 to 18 ° C., and immediately as shown in FIG. Is aligned with the printed wiring board 11 and brought into vacuum contact with the exposure unit 17 as shown in FIG. 6, and then UV exposure is performed with a light amount of about 200 to 250 mJ / cm ² .

Next, as shown in FIG. 5 (d), the solder resist forming mask film 13 and the printed wiring board 11 are evacuated and peeled off, and immediately the heating portion 1 as shown in FIG.
At 8, the printed wiring board 11 is irradiated and heated with near infrared rays or infrared rays 15 of 500 to 2000 nm so that the surface temperature of the printed wiring board 11 becomes 50 to 90 ° C. Then, Fig. 5
(E) and as shown in FIG.
1. The unexposed area of the solder resist ink for photographic development is developed and removed with a developing solution containing trichloroethane as a main component.

After that, a temperature of 130 to 1 is set in a hot air circulation tank or the like.
The final curing is performed under the conditions of 60 ° C. and time of about 30 to 60 minutes to stabilize the adhesion between the insulating substrate 11a, the conductor pattern 11b and the solder resist 12b.

As described above, according to the present embodiment, the photo-developing solder resist is applied to the printed wiring board by using the printed wiring board manufacturing apparatus provided with the cooling portion, the exposure portion, the heating portion and the developing portion. Steps of applying ink and drying by touching, cooling the printed wiring board, exposing the photographic development solder resist to a desired shape, heating the printed wiring board, and photographic development solder resist Depending on the process configuration for developing the ink, it is possible to improve the releasability between the solder resist ink for photographic development and the mask film for forming solder resist at the time of eliminating the standing cooling time after drying the finger and releasing the vacuum after UV exposure. Yes, no defects such as unexposed solder resist due to the adhesion of the solder resist ink for photographic development to the mask film for solder resist formation were observed, and the exposure time was halved. Also it is possible to remarkably improve the productivity in a significant reduction entire solder resist forming process such as the standing time until after exposure and development.

Although the printed wiring board 11 is a single-sided printed wiring board in the first, second, and third embodiments of the present invention, the printed wiring board 11 is a double-sided or multilayer printed wiring board. Although the photographic developing solder resist ink 12a is of the solvent developing type, it goes without saying that the photographic developing solder resist ink 12a may be of the alkali developing type.

[0036]

INDUSTRIAL APPLICABILITY As described above, according to the present invention, a step of applying a photographic developing solder resist ink to a printed wiring board and drying it by touch, a step of cooling the printed wiring board, and a photographic developing solder resist are desired. The process of exposing the shape, the process of heating the printed wiring board, and the process of developing the solder resist ink for photo development enhances the productivity of the solder resist forming process by the photo development method and significantly improves the manufacturing process yield. In addition, the reliability of the electronic device can be improved.

[Brief description of drawings]

1A to 1D are cross-sectional views showing a manufacturing process of a printed wiring board according to a first embodiment of the present invention.

FIG. 2 is a conceptual diagram of a printed wiring board manufacturing apparatus according to the first embodiment of the present invention.

3 (a) to 3 (d) are cross-sectional views showing a manufacturing process of the printed wiring board in the first embodiment of the present invention.

FIG. 4 is a conceptual diagram of a printed wiring board manufacturing apparatus according to a second embodiment of the present invention.

5 (a) to 5 (e) are cross-sectional views showing a process of manufacturing a printed wiring board according to a second embodiment of the present invention.

FIG. 6 is a conceptual diagram of a printed wiring board manufacturing apparatus according to a third embodiment of the present invention.

FIG. 7 is a conceptual diagram of a conventional printed wiring board manufacturing apparatus.

8A to 8D are cross-sectional views showing a process of manufacturing a conventional printed wiring board.

9A and 9B are sectional views showing the same manufacturing process.

[Explanation of symbols]

 11 Printed Wiring Board 11a Insulating Substrate 11b Conductor Pattern 12a Photographic Development Solder Resist Ink 12b Solder Resist 13 Solder Resist Forming Mask Film 14 Ultraviolet 15 Infrared 16 Touch-Drying Part 17 Exposure Part 18 Heating Part 19 Developing Part 20 Cooling Part

Claims (7)

[Claims] 1. A step of applying a photographic developing solder resist ink to a printed wiring board and drying by touching with a finger, and a step of exposing the photographic developing solder resist ink to a desired shape.
A method for manufacturing a printed wiring board, comprising the steps of heating the printed wiring board immediately after exposure and then developing a solder resist ink for photographic development. 2. The method for manufacturing a printed wiring board according to claim 1, wherein the heating means irradiates infrared rays or near infrared rays. 3. An exposed portion for exposing a solder resist ink for photographic development applied to a printed wiring board in a desired shape, and heating for heating the printed wiring board disposed immediately after this exposed portion and after exposure. And an apparatus for manufacturing a printed wiring board. 4. A step of applying a photographic developing solder resist ink to a printed wiring board and drying by touching, a step of cooling the printed wiring board, and a step of thereafter exposing the photographic developing solder resist to a desired shape. And a step of subsequently developing a solder resist ink for photographic development, the method for producing a printed wiring board. 5. A cooling unit for cooling a printed wiring board coated with a solder resist ink for photographic development, and an exposure unit disposed behind the cooling unit for exposing the solder resist for photographic development into a desired shape. At least a printed wiring board manufacturing apparatus. 6. A step of applying a photographic developing solder resist ink to a printed wiring board and drying by touching with a finger, a step of cooling the printed wiring board, and a step of thereafter exposing the photographic developing solder resist to a desired shape. A method for manufacturing a printed wiring board, comprising a step of heating the printed wiring board immediately after exposure and a step of developing a solder resist ink for photographic development thereafter. 7. The printed wiring board manufacturing apparatus according to claim 5, further comprising a heating portion which is provided immediately after the exposure portion and which heats the exposed printed wiring board.