(658f) Metalorganic Chemical Vapor Deposition of Ingaasn Using Dilute Nitrogen Trifluoride and Tertiarybutylarsine

The metalorganic chemical vapor deposition of In_0.07Ga_0.93As_1-xN_x, with x = 0.00 to 0.02, has been examined using nitrogen trifluoride and tertiarybutylarsine. The solid N/V ratio in the film increased linearly with the gas-phase N/V ratio up to 2.0% nitrogen at a gas N/V equal to 0.35. No further increase in nitrogen content could be achieved unless the feed rate of the group III sources was reduced. The growth rate decreased by about 40% with increasing NF₃ feed rate up to 3.0x10^-4 mol/min (N/V = 0.35). Further addition of NF₃ did not affect the growth rate, but caused the surface roughness to rise rapidly from 0.1 to over 1.0 nm. Experiments conducted in ultrahigh vacuum indicated that fluorine etching of the group III elements occurred when In_0.07Ga_0.93As_0.98N_0.02 was exposed to 1.0x10^-6 Torr NF₃ at 530 °C. Etching was accompanied by solid-state diffusion of the group III elements and indium segregation to the surface. These results indicate that for InGaAsN MOCVD with NF₃, nitrogen incorporation is limited to ~2.0%.