A Theoretical Study of Nitrogen‐Induced Effects on Initial Steps of Diamond CVD Growth

An investigation based on an ultra‐soft, pseudo‐potential, density functional theory (DFT) method, using a generalized gradient approximation (GGA) under periodic boundary conditions, is performed in order to investigate the effect of substitutional nitrogen on the CH3 adsorption and the H abstraction from the adsorbed CH3 species. Both (111) and (100)‐2x1 surface are considered with 4 and 6 substitutional N positions, respectively. For the two surface orientations, no strong effect of N is generally observed when positioning it within the first C layer (i.e., surface layer). The only exception is for N in one of three investigated first layer positions within the (100) surface, for which a spontaneous β‐scission occurs as a result of the H abstraction reaction. For N in the second carbon layer, the CH3 adsorption reaction is calculated to be strongly disfavored, whilst the H abstraction reaction is markedly improved.