The image reversal characteristics of SPP, which is composed of an alkali-soluble silicone polymer (APSQ) and a diazonaphthoquinone photosensitizer, have been studied. The mechanism of SPP image reversal in near UV lithography is the acid-catalyzed condensation of the silanol groups in the APSQ during postexposure baking. SPP is a dual-mode resist which can accommodate both a standard positive resist process and an image reversal process in near UV lithography. The sensitivity is much higher in the latter process.
No takes yet. Share an insight, caveat, or question.
Tanaka et al. (1989) studied this question.