nfluence of temperature on the formation of altered layer during silicon etching in CF₂Cl₂plasma

Abstract

Reactive ion etching of silicon in CF2Cl2 plasma is considered. During the experiment, silicon substrates are etched in CF2Cl2 plasma at temperatures of 320 and 390 K. Thickness of formed altered layers is measured using an X-ray photoelectron spectrometer. The thickness of the altered layer decreases with the increase in temperature. Extrapolation of experimentally measured concentrations of Si atoms in the altered layer is used to determine processes that influence the decrease of the thickness of the altered layer at a higher temperature. It is determined that the thickness of the altered layer decreases with the increase in temperature due to slowdown of the chemical reaction of CF2 radicals with Si atoms and intensified desorption of formed SiF4 molecules.