Phase diagram of the SrS–Ga 2S 3 system and its application to the single-crystal growth of SrGa 2S 4

Abstract

Ce-doped SrGa 2S 4 compound is expected as a new host material of blue EL devices. However, the basic properties of bulk single crystals have not been fully clarified, since this compound has been mostly synthesized in the form of polycrystals or thin films. Here, we firstly present the pseudo-binary phase diagram of the SrS–Ga 2S 3 system constructed in accordance with our DTA data for single-crystal growth of SrGa 2S 4. It is shown that SrGa 2S 4 compound has a congruent melting point and a eutectic reaction in the side of excess of Ga 2S 3 concentration. On the basis of the phase diagram, single crystals of SrGa 2S 4 are grown using Ga 2S 3 as a self-flux in a horizontal Bridgman furnace. Colorless and transparent crystals having a typical size 2×2×2 mm 3 are obtained.