Highly selective InGaAs growth by metalorganic chemical vapor deposition with a high-speed rotating susceptor

Abstract

Selective InGaAs growth using a metalorganic chemical vapor deposition (MOCVD) reactor with a susceptor that can be rotated at high speed is studied at various growth temperatures and growth rates. The high-speed rotating susceptor enables the selective growth of InGaAs at very low temperatures, about 200°C lower than in conventional selective MOCVD growth. The critical growth rate for selective growth can also be expanded to a much higher range with this technique. It is considered that the improved selectivity is due to the high velocity of the gas flow just above the susceptor caused by a high-speed rotation, which results in a low surface supersaturation ratio of adsorbed species on the mask. We also estimate the supersaturation ratios using a nuclei formation model with the change in Gibbs free energy. It is found that the supersaturation ratio at 1400 rpm is reduced to about one third of the ratio at 200 rpm.