Sensitivity/resolution variables in x-ray chemically amplified resists exposed to synchrotron radiation

Abstract

New formulations of chemically amplified negative-image photoresists show sensitivities to x rays on the order of 100 mJ/cm2 or less and printed minimum linewidths of 0.25 μm or smaller under electron-beam conditions. Under x-ray exposure, both the resist sensitivity and the contrast are responsive to the processing variables of post-exposure bake temperature, post-exposure bake time, developer normality, and developing time. Initial data are presented for Shipley XP-8933B and several experimental resists to illustrate the major relationships between the listed variables for x-ray exposure. Under optimum conditions all resists produce minimum linewidths of 0.4 μm or better.