GROWTH OF ERBIUM-DOPED GAAS AND INP BY METALORGANIC CHEMICAL VAPOR-DEPOSITION USING ER(CH3C5H4)3 AND ER(C5H5)3

Erbium-doped GaAs and InP layers are grown by low pressure metalorganic chemical vapor deposition at growth temperatures between 575 and 700°C using Er(C5H5)3 and a new source, Er(CH3C5H4)3. Erbium doping as high as 1019 cm-3 is realized at a source temperature as low as 100°C using Er(CH3C5H4)3, nearly 100°C lower than when using Er(C5H5)3. A fairly abrupt Er doping profile shows absence of a memory effect and no Er diffusion during growth is observed. GaAs:Er grown with Er(CH3C5H4)3 shows the same photoluminescence spectra as those grown with Er(C5H5)3. These spectra suggest the existence of various kinds of Er luminescent centers with similar crystal field symmetry. The Er-related photoluminescence intensity increases almost linearly with Er concentration up to 5×1018 cm-3, above which it decreases abruptly.