METHOD FOR FABRICATING BISMUTH GERMANIUM OXIDES CRYSTAL

摘要

PURPOSE: A fabrication method of bismuth germanium oxides crystal to exclude inclusion-induced crystalline defects is provided. CONSTITUTION: In a manufacturing method of bismuth germanium oxides crystal where seed crystals for bismuth germanium oxides come into contact with melt in crucible, the method includes step of charging 1500 g of starting material in the range of 39.2-39.7 mole% Bi2O3 in platinum crucible and subsequently melting the starting material by induction heat; contacting seed crystals for bismuth germanium oxides in 110 crystal direction with melt obtained in above step and subsequently pulling up the seed crystals at an elevation rate of 3.05 mm/h and at a rotation speed of 45 rpm in atmosphere; and separating the pulled-up bismuth germanium oxides crystal and subsequently cooling it at a cooling rate of 20 deg.C/h to obtain transparent bismuth germanium oxides crystal.