Dependence of carbon incorporation on crystallographic orientation of GaAs and AlGaAs grown by metalorganic chemical vapor deposition using CBr4

Abstract

The electrical properties of CBr4-doped GaAs and Al0.3Ga0.7As epilayers grown on GaAs substrates with various surface crystallographic orientations from (100) toward (111)A were investigated. Carbon incorporation into GaAs and AlGaAs epilayers was performed by atmospheric pressure metalorganic chemical vapor deposition using CBr4. The electrical properties of the epilayers showed a strong crystallographic orientation dependence. With an increase of the surface offset single, the hole concentration of CBr4-doped GaAs and AlGaAs epilayers rapidly decreased showing a hump at (311)A. The trend of the hole concentration dependence on the offset angle was not changed with growth temperatures in the range of 550-650 degrees C. Carbon incorporation is much higher in AlGaAs than in GaAs. (C) 1997 American Institute of Physics.