JPS5916433B2 - Method for forming patterns on insulating substrates - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (1) Technical Field of the Invention The present invention relates to a method for forming a pattern on an insulating substrate, and in particular, in the formation of a printed circuit pattern, a pattern is formed on an insulating substrate using a photosensitive dry film resist. ■) regarding the formation method.

f2,) Prior art and problems Photosensitive dry film resists are made of a resin material such as a Mylar film sandwiched together to protect the resist.
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When such a photosensitive dry film resist is used, one of the Mylar films is peeled off and the resist is laminated and adhered to a circuit forming board for subsequent pattern formation. However, when forming the pattern, the photosensitive dry film resist described above has the drawback that fine particles and other dust from the resist tend to adhere during exposure and printing of the circuit pattern.

Furthermore, if the foreign matter is present on the printed circuit board side, poor adhesion of the photosensitive dry film resist will occur. j5
This is believed to be due to the dust-collecting effect due to the electrostatic charge generated during the peeling of the Mylar film. FIG. 1 is a sectional view showing the state of a bright substrate laminated with a photosensitive dry film resist before exposure and printing.

In the figure, 1 is a printed circuit board, 2 is a conductive film for circuit pattern formation, 3 is a resist layer, and 4 is a protective Mylar film, and the resist layer 3 and Mylar film 4 are the photosensitive dry 25 film resist. Configure. Further, numeral 5 indicates dust accumulated on the front and back sides of the film. In order to eliminate the above-mentioned inconvenience, cleaning with a cleaning solution having a resist solvent composition in the illustrated state may be considered, but even with this method, for example, the patterning rate is high, with the 3o (I) circuit pattern being formed up to the edge of the substrate. In printed circuit boards, the laminated resist layer at the edge of the board is damaged or eluted.

(10) During the baking process, dust tends to re-adhere to resist laminate substrates due to the electrostatic phenomenon described in 35 above.

There is a problem. (3) Purpose of the invention The present invention aims to improve the quality and reliability of circuit patterns formed on printed circuit boards, and proposes a pattern forming method using a photosensitive dry film resist that is less likely to cause pattern defects and has a high patterning rate. It is.

(4) Structure and Embodiments of the Invention In order to achieve the above-mentioned object, according to the present invention, the photosensitive dry film resist before circuit pattern printing or the mylar of the resist layer laminate printed circuit board in the state shown in FIG. The surface of the film is treated with an antistatic base material, which is a chemical that reduces surface insulation resistance and prevents static electricity accumulation, by coating, spraying, or other means.

The antistatic effect on the surface need not be permanent; therefore, the surface is treated with a water-soluble surfactant as described below before printing the circuit pattern photograph.

As the water-soluble surfactant, Na laurylaminopropionate (1aUryLaminOprOplOnat
e), DEA steaririminodepropionate (St
earlyLiminOdiprOpiOnate) etc. can be applied.

However, in addition to the above-mentioned surfactants, chlorosilane, hydrolysis products of silicon tetrachloride, etc. are also effective in significantly reducing the charge accumulation effect on the surface of plastic film. Then, the film resist laminate circuit board that has undergone the above-mentioned processing is exposed and printed using a circuit pattern mask (not shown).

After such exposure and baking, the Mylar film 4 on the surface was removed, and then development was performed to selectively remove the unnecessary resist layer 3', and the state in which the circuit pattern was formed is shown in FIG.

Thereafter, a chemical etching process is performed on the circuit conductor film 2 on the printed circuit board 1 using the resist layer 3 as a mask, and the resist layer 3 is further eluted to form a circuit pattern 27.

Such a state is shown in FIG. (5) Effects of the Invention According to the antistatic treatment method for a photosensitive dry film resist of the present invention, a highly reliable circuit pattern with few defects can be formed by an extremely simple means, and a printed circuit board with a high patterning rate can be formed. Effective for manufacturing.

[Brief explanation of the drawing]

FIG. 1 is a sectional view illustrating printed circuit board forming means using a photosensitive dry film resist, and FIGS. 2 and 3 are sectional views illustrating a circuit pattern forming process. In the figure, 1 is a printed circuit board, 2 is a conductor film for forming a circuit pattern, 3 is a resist layer, 4 is a resin film, and 5 is foreign matter such as dust.

Claims (1)

[Claims] 1. A method for forming a pattern on an insulating substrate, in which a conductive layer formed on the insulating substrate is selectively etched using a photosensitive dry film resist as a mask to form a conductive pattern on the insulating substrate. A method for forming a pattern on an insulating substrate, characterized in that the photosensitive dry film resist is subjected to antistatic treatment before pattern baking.