Growth improvement and characterization of AgGaxIn1−xSe2 chalcopyrite crystals using the horizontal Bridgman technique

AgGaxIn1−xSe2 single crystals with x=0.4 have been grown by the horizontal Bridgman technique for nonlinear optical application requires phase matching. High purity polycrystalline synthesis of AgGaxIn1−xSe2 was carried out at 850 °C, which is a relatively lower temperature compared to those in earlier reports, thus reducing secondary phase formation. An average Ga:In ratio of 62:38 (±3%) was measured using energy dispersive spectroscopy (EDS). As grown, a single crystal shows very high IR transmission of ∼65% in the spectral range of 4000–600 cm−1. There was no significant change in its IR transmission after annealing it at 500 °C for 20 days in vacuum in the presence of AgGaxIn1−xSe2 powder. This indicates a low concentration of defects in the crystal. The results demonstrate that the improved new synthesis method for crystal growth was promising and that the quality of the crystal was good.