Atomistic modeling of morphological evolution during simultaneous etching and ox

2020-02-12 14:25:42

Si oxidation etching Oxygen oxide

责任者: Albao, M.A.;Da-Jiang Liu;Choi, C.H.;Gordon, M.S.;Evans, J.W. 单位: Ames Lab., Iowa State Univ., Ames, IA, USA 来源出处: Surface Science(Surf. Sci. (Netherlands)),2004/04/20,555(1-3):51-67 摘要: Prolonged exposure of Si(100) surfaces to oxygen produces: etching at high temperatures (T) characterized by the formation of monolayer-deep elliptical etch pits in successive layers (active oxidation); simultaneous etching and formation of oxide-capped Si-nanoprotrusions at moderate T (transition regime); and rapid coverage of the substrate by an oxide layer at low T (passive oxidation). We develop an atomistic model with the goal of describing evolution of the complex far-from-equilibrium surface morphology for a range of temperatures above and into the transition regime under conditions where etching dominated oxidation. Model development is guided by experimental observations, by general concepts from nucleation theory for the formation of etch pits and oxide islands, and by input from ab-initio quantum chemistry calculations for key aspects of the oxygen adsorption and SiO desorption energetics 关键词: ab initio calculations;adsorption;desorption;elemental semiconductors;etching;island structure;monolayers;nucleation;oxidation;oxygen;silicon;silicon compounds;surface chemistry;surface morphology;vacancies (crystal);atomistic modeling;morphological evolution;etching;oxidation;monolayer deep elliptical etch pits;oxide capped Si nanoprotrusions;atomistic model;equilibrium surface morphology;nucleation theory;oxide islands;ab initio quantum chemistry calculations;oxygen adsorption;SiO desorption energetics;divacancies;O;Si;SiO