GROWTH OF CU(ALXGA1-X)SSE PENTENARY ALLOY CRYSTALS BY IODINE CHEMICAL-VAPOR TRANSPORT METHOD

Single crystals of Cu(AlxGa1-x)SSe pentenary alloys were successfully grown by the vapor transport technique using iodine as a transport age nt. Systematic measurements of the basic crystal properties were carri ed out using powder X-ray, photoluminescence (PL), photoreflectance (P R), and Van der Pauw methods. Dependence of the lattice constants, exc iton transition energies, and PL peak energies on Al composition, x, w ere examined in detail. The lattice constants obeyed Vegard's law. A q uadratic dependence of exciton transition energies on x was found. The broadening parameters in the PR spectrum increase monotonically with increasing x, the results showing that the crystal quality degrades wi th increasing x. Exciton-related PL peaks were found for 0 less-than-o r-equal-to x less-than-or-equal-to 0.77 at 77 K.