Abstract: CdGeAs₂ polycrystal was synthesized by the raw materials of 99.9999% Cd, Ge and As in stoichiometric weights with proper excess of Cd and As through mechanical and temperature oscillation of melt(MTOM). An integral, crack free CdGeAs₂ single crystal with size of 15 mm×40 mm was obtained by modified vertical descending cubic technique. The CdGeAs₂ polycrystal and as-grown crystals were characterized by X-ray diffraction and infrared spectroscopy. XRD riteveld analysis indicates that the synthetic product is high-purity CdGeAs₂ polycrystal in chalcopyrite structure, the lattice constants of a and c are 0.5946nm and 1.1217nm, respectively. The as-grown crystal is integrated in structure and crystallized well. It is also found that the cleavage plane of the crystal is (101). CdGeAs₂ wafer with 1.0 mm thickness is transparent in range of 589-4250cm^-1, and the band width is calculated to be 0.67eV.

Key words: CdGeAs₂, synthesis, single crystal growth, XRD analysis, IR transmission spectrum