Production manner null of barium titanate

摘要

PURPOSE: To produce BaTiO₃ capable of stably showing a large optical refraction due to its hole-dominancy. ;CONSTITUTION: A mixture of titanium dioxide with barium oxide or carbonate is mixed with one or more transition metal elements selected from the group consisting of V, Cr, Mn, Fe, Co, Ni and Cu in a total amount of more than 2ppm to be used as a starting material. The material is molten by heating at a prescribed temperature to prepare a melt 6. A seed crystal of BaTiO₃ 7 is brought into contact with the melt 6 in the atmosphere of a low oxygen partial pressure less than 0.2 atmospheric pressure to effect the growth of a single crystal on the surface of the seed crystal. Then, the resultant single crystal is heat-treated at a temperature over 600°C in an oxidative atmosphere of more than 0.02 atmospheric pressure of oxygen partial pressure.;COPYRIGHT: (C)1993,JPO&Japio