DETERMINATION OF THE BONDING OF CARBON ACCEPTORS IN INXGA1-XAS FOR X-LESS-THAN-0.1

The local environment of CAs acceptors in InxGa1-xAs has been determined from the localized vibrational modes (LVMs) of both isolated CAs impurities and H-CAs pairs using infrared (IR) absorption and Raman scattering techniques. In as-grown layers, a single LVM due to CAs was observed which broadened and shifted to lower energies with increasing x. The introduction of hydrogen led to the formation of H-CAs pairs and a single antisymmetric A1- mode (stretch) and a single symmetric A1+ mode (XH) were observed for all samples. All the LVMs were identified with carbon in CAsGa4 cluster configurations implying that less than 5% of the detectable carbon atoms are present in clusters incorporating one or more CAs-In bonds.© 1995 American Institute of Physics.