Applicability of one-dimensional diffusion model for step coverage analysis—Comparison with a simple Monte Carlo method

Abstract

Applicability of a one-dimensional reaction-diffusion model (ORDM) as a tool for analyzing the gas–solid phase transition rate process during chemical vapor deposition is tested by comparing its results with those predicted by a simple Monte Carlo method. The results reveal that the ORDM is applicable when the conditions of Knudsen number (Kn)<0.03, aspect ratio (As)≳1.0, and reactive sticking coefficient (η)<0.1 are fulfilled. At large Kn and large η, the ORDM gives quite an erroneous result. The ORDM is also applicable to predict the grown film shape when η<0.1, Kn ≫1.0, and As≳2.0.