Growth of single-phase CuInGaSe2 photo-absorbing alloy films by the selenization method using diethylselenide as a less-hazardous Se source

Selenization growth of purely single-phase, polycrystalline CuIn1 − xGaxSe2 (0 ≤ x ≤ 1) alloy films was demonstrated using a less-hazardous metalorganic selenide, diethylselenide [(C2H5)2Se: DESe], without additional thermal annealing. Approximately 2.0-μm-thick films of the alloys exhibited X-ray diffraction peaks originating exclusively from the chalcopyrite structure. Low temperature photoluminescence spectra of the alloy films were dominated by a couple of characteristic donor-acceptor pair emissions that are particular to the state-of-the-art CuInGaSe2 photo-absorbing layers.