Properties of Epitaxial Gallium Arsenide from Trimethylgallium and Arsine

Electrical and optical properties of epitaxial layers grown from trimethylgallium and arsine were studied by Hall and photoluminescence measurements. The conduction type of the layers grown on substrates was changed from p‐ to n‐type with increase of , the mole ratio of arsine to trimethylgallium introduced, without intentional doping. An emission (P 2 ) at 1.488 eV due to shallow acceptors was observed on most of the samples. Correlations between the carrier concentration and the intensity of the P 2 emission with suggest that the main acceptor impurities in the epitaxial layer are amphoteric ones on As sites, such as carbon and silicon contained in the trimethylgallium source. Results of the mass‐spectrographic analysis of the layers are consistent with the above suggestion.