Plasma polymerized organosilane network polymers: high-performance resists for positive- and negative-tone deep-UV lithography

Abstract

We recently introduced a new class of high performance deep-UV photoresists which are deposited via the gas phase plasma polymerization of methylsilane. These materials, particularly plasma polymerized methylsilane (PPMS), undergo efficient oxidation on exposure to deep-UV light in air to form a glasslike siloxane network polymer, providing patterns which may be developed and transferred into underlying substrates using all dry plasma etch processes. Here we describe a simple new procedure which affords the opposite (positive) tone image in the same resist using a wet buffered oxide etch to remove exposed regions. Lithographic performance studies (dose latitude as well as linearity data) are presented for both the negative tone and the new positive tone versions of the process.