High-aspect-ratio resist pattern fabrication by alkaline surface treatment

Abstract

A new and simple high‐aspect‐ratio, single‐layer resist process for the manufacture of very large scale integration (VLSI) devices is described. Before the exposure step in the conventional process, an alkaline surface treatment is added to the positive photoresist. This treatment inhibits the dissolution of the unexposed resist layer during development, which leads to a high‐aspect‐ratio resist pattern. Excellent submicron resist patterns are obtained with a large focus latitude using this simple method.