Surface orientation dependency for AlGaAs growth rate with/without HCl in MOCVD

摘要

The growth rate dependence of Al_xGa_(1-x)As on surface orientation, Al composition, HCl introduction and growth temperature was investigated in metal-organic chemical vapor deposition. The Al_xGa_(1-x)As growth rate dependence on surface orientation and growth temperature were found to be similar to results found for GaAs independent of the Al composition. The effects of HCl introduction on growth behavior were dependent on the Al composition and growth temperature. The formation of metal chlorides, due to gas phase reactions between the source materials and HCl, can lead to different surface diffusion characteristics and affect the rate of metal atom incorporation into the growing crystal. This change in reaction and transport rates, coupled with the presence of the etching reaction from between the HCl and growth surface leads to improvement in selective area growth with HCl introduction.