New positive-type photoresists based on enzymatically synthesized polyphenols

New positive-type photoresist systems based on enzymatically synthesized polyphenols have been developed. The photoresist thin film consisting of the polyphenol and a diazonaphthoquinone derivative was prepared on copperfoil-coated epoxy resins and exposed to UV light with different doses. The polyphenols from the bisphenol monomers exhibited high photosensitivity, comparable with a conventional cresol novolac. The sensitivity could be controlled by changing the structure of the polyphenols. Furthermore, the present photoresist showed excellent etching resistance.