A Comparative Performance of Test Dry Film Photoresists on Stainless Steel
The objective of this study was to determine and quantify dry film photoresist performance differences in a photochemical machining application under standard processing conditions. Important performance criteria were yield and productivity through exposure. Five dry films in the thickness range of 0.6 to 1.5 mils (I5 to 38J.1rn) were tested vs. the incumbent 30J.1m thick photoresist. Optimization of processing conditions for the best-performing film was not part of this study but is intended to be the objective of a follow-up study. The commercial names ofthe dry film photoresists were changed to code names A, B. C etc. for the purpose of this publication. Thickness designations in mils were made part ofthe code, e.g., AI.3 is the 1.3mil thick incumbent film, 00,6 is a 0.6mil thick test film, and CI.3 and C1.5 are test films ofthe same composition but of different thicknesses.
Andrew Sauciunac and Darryl Switzer, Precision Photo Fab, Inc., and Karl H. Dietz, DuPont Printed Circuit Materials Group