Аннотация:The growth rate of diamond by chemical vapor deposition (CVD) from microwave (MW)plasma activated CH4/H2 gas mixtures can be significantly enhanced by adding tracequantities of N2 to the process gas mixture. Reasons for this increase remain unclear. Thepresent article reports new, self-consistent two-dimensional modeling of MWactivated N2/H2and N2/CH4/H2 plasmas operating at pressures and powers relevant to contemporary diamondCVD, the results of which are compared and tensioned against available experimental data.The enhanced N/C/H plasma chemical modeling reveals the very limited reactivity of N2under typical processing conditions and the dominance of N atoms among the dilute ‘soup’ ofpotentially reactive N-containing species incident on the growing diamond surface.Ways inwhich these various N-containing species may enhance growth rates are also discussed.