Surface smoothing during plasma etching of Si in Cl2

Effects of initial roughness on the evolution of plasma-inducedsurface roughness have been investigated during Sietching in inductively coupled Cl2plasmas, as a function of rf bias power or ion incident energy in the rangeEi ≈ 20–500 eV. Experiments showed that smoothing of initiallyrough surfaces as well as non-roughening of initially planarsurfaces can be achieved byplasma etching in the smoothing mode (at highEi) with some threshold for the initial roughness, above which laterally extended crater-like features were observed to evolve during smoothing. Monte Carlo simulations of thesurface feature evolution indicated that the smoothing/non-roughening is attributed primarily to reduced effects of theion scattering or reflection from microscopically roughened featuresurfaces on incidence.

Source: Applied Physics Letters - November 14, 2016 Category: Physics Authors: Nobuya Nakazaki, Haruka Matsumoto, Hirotaka Tsuda, Yoshinori Takao, Koji Eriguchi and Kouichi Ono Source Type: research