NMR analysis of chemically amplified resist films

Abstract

Carbon-13 nuclear magnetic resonance (NMR) spectroscopy has been employed in the investigation of ESCAP-related deep UV resist films. The films were first processed (baked and/or exposed) and then dissolved in a deuterated solvent. Quantitative data were obtained on the concentration of residual casting solvents as a function of the bake temperature and of storage conditions. In addition to accurate determination of the degree of deprotection, side reactions that occur in the resist film such as C- and O-alkylation of the phenol have been quantitatively analyzed while varying the exposure dose, bake temperature, resin structure, and acid generator. Furthermore, photochemical decomposition of several acid generators in the resist film was quantitatively monitored. This paper demonstrates that the 13C NMR technique can readily provide a wealth of quantitative and indispensable information about constituents and chemistries in resist films.