Modeling of the high aspect groove etching in Si in a Cl2/Ar mixture plasma

Abstract

The model and the results of the modeling of etching deep grooves in Si in Сl₂/Ar plasma as a function of the energy of Cl⁺ and Ar⁺ incident ions (30–250 eV), taking into consideration the redeposition of the reaction products, which are removed from the groove bottom, are represented. The groove profiles with an aspect ratio (depth-to-width groove ratio) below 5 and Si atom yield coefficients per ion as a function of the incident ion energy were in agreement with the reference data. The profile evolution of the deep grooves with an aspect ratio (AR) of up to 10 at different energies of the incident ions is shown. The influence of the redeposition coefficient of the scattered particles and the shape of the mask on the groove profile is considered. The reasons for distorting the profile of the high-aspect grooves during their etching in the Сl₂/Ar plasma are discussed.