Study on phase diagram of Bi2O3-SiO2 system for Bridgman growth of Bi4Si3O12 single crystal

Phase relation of Bi2O3-SiO2 system was evaluated experimentally from DTA and XRD measurements and its stable and metastable phase diagrams were proposed. Although BSO melts near-congruently at 1025 degrees C in the stable phase equilibrium its melt crystallizes to form metastable phase Bi2SiO5 in accordance with the metastable phase diagram while cooling Therefore, BSO couldn't nucleate and crystallize spontaneously without crystal seed and only Bi2SiO5 crystallized at about 850 degrees C with significant supercooling during Bridgman growth. BSO single crystal with 20x20x100mm(3) was grown in a vertical Bridgman furnace with a BSO seed according to its phase diagram The measuring results of scintillation properties of BSO specimen show that its decay constant is 91 ns (about 1/3 of EGO) and light output is 23% of EGO.