I am looking for a dry film photoresist suitable for lift-off processing
of Ni-Cu thin film (UBM) layers that are evaporated onto aluminum. Liquid
photoresists are not options since the silicon wafer substrate has
numerous deep vias etched into it.
I've tried DuPont's Riston CM206 but the stripper for that product, NaOH,
etches aluminum and hence is not compatible. Other solvents (acetone,
methanol, IPA, Shipley 1165 resist stripper) have proved ineffective in
stripping the film.
Ideally, the film thickness would be between 5 and 20 microns.
Development must provide sufficient resolution for the opening of
300micron diameter circular holes in the film. Developer and stripper
chemistries should be compatible with Al, Ni & Cu. Good adhesion to
aluminum is also desired. Vacuum lamination or other application methods
are fine.
Does anyone have experience with other dry film photoresists that may work
in this application? Any suggestions or comments would be appreciated.
Sincerely,
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Jordan M. Neysmith Off: MARC Room 441
Mechanical Engineering Ph: (404) 894-1460
Georgia Tech Fx: (404) 894-9342
327009 GT Station Atlanta, GA 30332 (404) 874-2911
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