Modeling the Charging Effect on the Twisting Defects During High Aspect Ratio Etching of Dielectrics

In high-aspect-ratio (HAR) plasma etching of dielectrics, random twisting is frequently observed. The charging effect is considered a potential factor influencing this twisting. We develop a novel model that takes into account the charging effect to simulate the profile evolution of SiO<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</inf> layers and potential distribution during nanoscale HAR etching. The model also explores the effect of charging effect on twisting defects.