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Abstract: CdTe films with a thickness of 100μm were grown by molecular beam epitaxy (MBE) on semi-insulating LEC GaAs (001) substrates. The films were characterized by X-ray diffraction (XRD), photoluminescence (PL), X-ray photoelectron spectroscopy (XPS), I/V characteristics and detector measurements using a 241Am source. The grown layers were highly oriented as revealed from X-ray pole figure measurements and high-resolution XRD experiments. Low temperature PL measurements showed the formation of A-center complexes including Ga and In acting as donors. Furthermore, the distribution of these impurities in the films was determined by spatially resolved PL measurements. XPS demonstrates the formation of a TeO2 overlayer due to Cd depletion at the surface of the films. The electrical measurements including I/V characteristics and detector measurements resulted in resistivity values of around 3×108 Ωcm and a μt product of electrons of 10−5 cm2/V. [Copyright &y& Elsevier]

100 µm thick films of CdTe were grown on semi-insulating (100) GaAs substrates by Physical Vapor Transport (PVT) in a modified Molecular Beam Epitaxy facility. The grown layers were highly oriented as revealed from X-ray pole figure measurements. Temperature- and intensity-dependent photo-luminescence measurements were taken before and after the chemical removal of the substrate to determine the effect of the GaAs substrate and to estimate the crystallographic quality of the layers. Current-voltage characteristics were performed to obtain the resistitivity of the layers with 108cm. [ABSTRACT FROM AUTHOR]