PROCESS FOR PRODUCING LITHIUM TANTALATE CRYSTAL

摘要

A process for producing lithium tantalate crystal, characterized in that the process includes at least superimposing a first original material containing lithium tantalate or lithium niobate or a hydrogen storing hydrogen storage metal, having been heat treated at temperature (T1') not lower than Curie point in a reducing atmosphere, on a monopolarized lithium tantalate crystal and performing heat treatment of the laminate at temperature (T2') lower than Curie point in a reducing atmosphere so that the electrical conductivity of the monopolarized lithium tantalate crystal is increased. Thus, not only can the surface charges generated by exposing the lithium tantalate crystal to a temperature change be dissipated without being accumulated by the increase of electrical conductivity of the lithium tantalate crystal but also a process for producing lithium tantalate crystal capable of maintaining monopolarized structure and exhibiting effective piezoelectricity can be provided.