The C doping efficiency in samples grown via metalorganic chemical vapor deposition by using intrinsic and extrinsic doping sources was studied. Regardless of the C source, CH complexes were always present and, depending upon the growth conditions, C dimers could be present and also form complexes with H. The C–H related complexes and dimers reduced the hole concentration and decreased the doping efficiency. Moreover, the C dimer introduced a deep level, decreased hole mobility and H bonded stronger to it than it did to isolated C. Depending upon the growth conditions, it was possible to attain 100% doping efficiency with a high hole mobility.

Carbon Acceptor Doping Efficiency in GaAs Grown by Metalorganic Chemical Vapor Deposition. J.Mimila-Arroyo, A.Lusson, J.Chevallier, M.Barbé, B.Theys, F.Jomard, S.W.Bland: Applied Physics Letters, 2001, 79[19], 3095-7