| Abstract: | We have investigated the intrinsic C‐incorporation during the metalorganic vapour‐phase epitaxy of GaAs, (Al,Ga)As, and AlAs. The carbon from the methyl radicals of trimethylgallium and trimethylaluminium has been used as intrinsic carbon source and the necessary growth conditions (low growth temperatures and low V/III‐ratios) have been determined. Under these conditions we observed a reduction of the Al‐incorporation in (Al,Ga)As resulting from a change of surface kinetics at low temperatures. We have used the tensile tetragonal lattice distortion due to the C‐incorporation for determination of the carbon concentration. This has been done by investigating the symmetric (004) reflection peaks of GaAs and the strained epitaxial layer by high resolution x‐ray diffraction. The resulting carbon concentrations showed a good agreement with the hole concentrations determined by Hall measurements and spectroscopic ellipsometry. |
