Sequential infiltration synthesis (SIS) is a promising method for organic-inorganic hybridization of organic polymer resist films in nanolithography. The understanding of the distribution of inorganic components in hybrid films is necessary for the practical use of SIS-treated resist films. In this study, we investigated the distribution of aluminum oxide in SIS-treated positive-tone electron beam resist films of poly(methyl methacrylate) and ZEP520A with thicknesses of 100, 40, and 20 nm by time-of-flight secondary ion mass spectrometry (TOF-SIMS). TOF-SIMS profiles revealed that the aluminum species of AlO- and AlO2 - derived from aluminum oxide existed heterogeneously near the air/polymer surface, film inside, and polymer/substrate interface, and the distributions of respective species depended on film thickness. TOF-SIMS enabled the characterization of aluminum distribution in 20 nm thick resist films. It was suggested that the oxidation states of Al components were different between near the air/polymer surface and near the polymer/substrate interface.
ASJC Scopus subject areas
- Physics and Astronomy(all)