Heavy carbon doping in metalorganic chemical vapor deposition for GaAs using a low V/III ratio

Abstract

Heavily carbon-doped GaAs was obtained by low-pressure metalorganic chemical vapor deposition by using trimethylgallium and arsine with a low V/III ratio. The hole concentration became as high as 2×1019 cm−3 without using intentional doping source gases when the V/III ratio was decreased to 2.4. The hole concentration coincided with the carbon concentration measured by secondary-ion mass spectroscopy. The epilayer surface tended to be rough when the V/III ratio was decreased below 10. However, when the V/III ratio was lowered to 2.4, the epilayer surface became completely mirror-like.