Quantitative Measurement of Pattern Collapse and Particle Removal Force

Abstract

The pattern collapse and the particle removal force should be quantitatively understood and measured to develop the effective cleaning process without pattern damages. The method of measuring these forces by atomic force microscope (AFM) was introduced in this paper. Pattern collapse forces of a silicon oxynitride (SiON), silicon oxide (SiO2) and photoresist (PR) line pattern were measured. The particle removal force was measured on a 100 nm PSL particle on silicon. The force for pattern collapse increased linearly as a function of pattern width. PR pattern requires a smaller force than the SiON and SiO2 pattern at the same line width. Particle removal force of aged PSL on hydrophilic Si surface was two orders smaller than the collapse force of same size of patterns.