Abstract
The chemistry and some performance aspects of a novel chemically amplified positive tone photoresist system sensitive to KrF excimer laser radiation is described. The material consists of three components: an α, α-bisarylsulfonyl diazomethane as the photoacid generator (PAG), an oligomeric N, O-acetal as the acid sensitive dissolution inhibitor (DI), and a poly(vinylphenol) as the hydrophilic matrix resin (MR). The material combines high photospeed through the chemical amplification mechanism with some properties of the conventional dissolution inhibition resist systems, such as standard processing and development conditions, excellent resolution, good contrast, favorable plasma etch stability, and easy stripping. Problems arising from the concept of chemical amplification, viz., delay time stability, formation of T-tops, and linewidth variation upon extended storage intervals are discussed, and first measures to their suppression will be presented. Some micrographs demonstrate the outstanding pattern quality of this newly developed resist material.
