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Photoluminescence (PL) study is performed on epitaxial layers of CuGaSe2 and CuAlSe2 grown by metalorganic chemical vapor epitaxy on CuGa0.96In0.04Se2 (CGIS) substrates prepared by traveling heater method (THM). The results show that the (THM-CGIS) single crystal has sufficient crystal quality as the substrate for the metalorganic vapor phase epitaxy (MOVPE) growth, and that for both CuGaSe2 and CuAlSe2 epilayers grown on CGIS(100) substrates include a small number of nonradiative recombination centers.

Chalcopyrite semiconductor copper gallium sulphide layers were grown on GaAs and GaP substrates using metalorganic vapor phase epitaxy.

A study was conducted on the phonon modes in the ZnGeP2 crystal belonging to the II-Iv-V2-type compounds. The polarized Raman spectra measurement in the crystal has been estimated, the symmetry of the phonon modes has been assigned and the angular dispersion of the extraordinary phonon has been examined. Among other experimental results, it was found that the frequency and vibration symmetry of one Raman active mode could not be determined. Other results are discussed.

Synchrotron radiation aids in extended X-ray absorption studies of the local structure of CuInSe2 thin films on Cu K and Se K edges. These studies, performed over a range of In/Cu ratios indicate a similarity between local structure and overall crystal structure. The bond between Cu-Se is not as strong as the In-Se bond, as revealed by temperature dependencies of relative mean-square displacements. Chemical disorder and anion vacancies lead to changes in bond lengths, causing distortion of the thin film structure.

Presents a study that examined the liquid-phase epitaxy (LPE) growth of indium-gallium-phosphorus-arsenic grown on gallium arsenide substrate under various growth conditions over the whole solid composition range. Growth of the LPE layers in the composition region influenced by immiscibility; Role of the elastic energy induced from a substrate; Degree of immiscibility.

Selective doping of a Zn impurity at the group III site in a Cu(In, Ga)Se2 (CIGS) film was performed by the doping of Zn at the first stage of the three-stage method. The p-type CIGS:Zn film was obtained, which is in contrast to the n-type CIGS:Zn film obtained by the Zn impurity doping at the second and third-stages. Based on excitation intensity dependence of photoluminescence (PL) at low-temperature, the change in the acceptor level was observed. The enhancement of carrier concentration as a result of Zn-doping in the p-type CIGS:Zn film was observed. The CIGS:Zn solar cells exhibited η of 14.5% and Voc of 0.658 V, which are higher than that of the corresponding solar cells using the undoped CIGS films [ABSTRACT FROM AUTHOR]

X-ray Fluorescence Holography (XFH) study of Cu(In,Ga)Se2 single crystals has been performed using an inverse mode. Energies of incident X-ray are from 9.2 to 13.2 keV. The Cu-Kα X-ray fluorescence hologram has been constructed, and atomic images were reconstructed using Barton's algorithm. Dependence of fluorescent X-ray, either Cu or Ga, on the reconstructed atomic images of CuIn0.2Ga0.8Se2 was examined. The atomic image of CuIn0.2Ga0.8Se2 was compared with that of CuIn0.8Ga0.2Se2. The reconstructed atomic images of the cation (Cu, Ga, and In) plane and that of the anion (Se) plane are discussed in terms of the alloy composition. [ABSTRACT FROM AUTHOR]