Numerical simulation study on growth rate and gas reaction path of InN-MOCVD with Close-Coupled showerhead reactor

Abstract

Numerical study on the influence of the carrier gas (H2 and N2), V/III ratio, inlet temperature, and pressure on gas reaction path and growth rate of indium nitride (InN) thin film in metal–organic chemical vapor deposition (MOCVD) with close-coupled showerhead (CCS) reactor was conducted. It was found that the concentrations of precursor for InN film and nanoparticle determine the growth rate and gas reaction path. InN exhibits greater difficulty in undergoing pyrolysis reactions compared to AlN and GaN. Under the conditions of this study, the gas reaction path of InN-MOCVD be dominated by adduct/amide formation path. When H2 is used as the carrier gas, the effect of H radicals on gas reactions is relatively minor, while the effect of NH2 radicals generates more nanoparticles, and significant changes in flow fields are observed compared to using N2 as the carrier gas. Under the conditions of low V/III ratio, low inlet temperature, high pressure, and low gas flow rate, the growth rate is relatively high, but the growth uniformity is decreased. There are different reasons for the effects of the above parameters, such as, altering TMIn flow to change V/III ratio and precursor concentration, varying temperature gradient due to changes in inlet temperature, and increased the particle collision frequency and residence time due to high pressure and low gas flow rate.