Abstract

A method for etching a polyimide body which involves directing U.V. radiation having a wavelength between about 240 to 400 nm. onto the body is described. The radiation is continued to be applied to the body for sufficient time to cause a direct etching of the body where the radiation impinges upon the body. The method is particularly useful where the U.V. radiation is passed through a mask located between the source of the ultraviolet radiation and the body so that a radiation pattern is projected onto the body where the direct etching takes place. The etching can be caused to produce openings having a positive slope in the radiation pattern upon the polyimide layer. The advantage of the positive slope is particularly great where a coating such as a metal layer is deposited over the remaining polyimide layer having the openings therein. The positive slope allows the complete filling of the openings.

Other References

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