Phase equilibria in the Cu-Ga-S-Sn system

Solid-liquid equilibria in the Sn-rich region of quaternary Cu-Ga-S-Sn system have been investigated experimentally. Solidus compositions corresponding to Cu-Ga-S-Sn liquidus points were determined using the crystals self-nucleated from solutions composed of Sn solvent and Cu-Ga-S solute. It has been found that, in the isothermal liquidus surface at 780°C, there exist at least four regions corresponding to different crystalline solids, having compositions of CuGaS₂, SnS, CuGa₃S₅ and Ga₄SnS_x (x=7∼8), respectively. The conditions of the solution growth of single-phase CuGaS₂ crystals using Sn solvent have been also discussed.