Carbon doping in GaAs using trimethylarsine by metalorganic chemical vapor deposition with high-speed rotating susceptor

Abstract

We have investigated carbon (C) doping in GaAs using trimethylgallium (TMGa) and trimethylarsine (TMAs) by metalorganic chemical vapor deposition (MOCVD) with a high-speed rotating susceptor. The dependence of hole concentration on the growth temperature and V III ratio is systematically investigated. Carbon incorporation characteristics are shown to be much different from those for conventional MOCVD. They are explained by assuming that C atoms are incorporated from TMGa and that the C-incorporation rate is dominated by As coverage on a substrate surface. The behavior of hole mobility, the lattice constant, and hole concentration distribution in a 3-inch wafer are also clarified. Superior hole concentration uniformity over the wafer has been achieved using TMGa and TMAs resulting from C incorporation which is less sensitive to the V III ratio at low growth temperatures.