Fine Pattern Etching of Silicon Substrates Using Atmospheric Line-Shaped Microplasma Source

Abstract

An atmospheric line-shaped microplasma source was developed for fine pattern etching, and the dependence of the etching properties on the substrate temperature and the distance between the two outer gas outlets was investigated. There was a sudden increase of the etching rate and a decrease of top width when the substrate temperature was 300°C or more. Auger electron spectroscopy (AES) analysis indicates that oxidation on the line shoulder caused the top width to decrease. By decreasing the distance between the two outer gas outlets from 3 mm to 650 µm, the top width decreased from 441 µm to 234 µm. The gas flow simulation result revealed that there exists a firing limit of SF 6 partial pressure from 0.1% to 0.2% in the configuration.