Simulation of Complex Resist Pattern Collapse with Mechanical Modeling

Abstract

High aspect ratio resist patterns with dimensions below 100 nm often bend, break or tear. These phenomena are generically called "resist pattern collapse". Pattern collapse is a very serious problem in fine patterning of less than 100 nm critical dimension (CD), so that it decreases the yield. In order to mechanically analyze this phenomenon and create its simulator, two models have been made and compared. In this paper, various approaches with various analyses are made to understand pattern collapse. Also, the critical aspect ratio for 100 nm node, that determines whether pattern collapse happens or not, can be calculated with these approaches. Finally, tear type caused by insufficiency of adhesion strength between the substrate and the resist is analyzed with a point of view of the surface free energy.