Crystal growth and characterization of Cu₂-II-IV-S₄ compound semiconductors

Abstract

We have invetigated the synthesis of Cu₂-II-IV-S₄ quaternary compounds (II=Zn, Cd; IV=Ge, Sn). The single phases were obtained, and melting points and crystal structures of the phases were determined using the differential thermal analysis and X-ray diffraction. Among these compounds, bulk crystals of Cu₂ZnSnS₄ and Cu₂CdSnS₄ were grown by the horizontal gradient freezing method. Optical band gaps of both Cu₂ZnSnS₄ and Cu₂CdSnS₄ were determined by optical absorption measurements to be 1.38eV.