LITHIUM TANTALATE SUBSTRATE AND FABRICATING METHOD THEREOF TO PREVENT COMB PATTERN FORMED ON SUBSTRATE FROM BEING BROKEN AND AVOID DAMAGE TO LITHIUM TANTALATE SUBSTRATE

摘要

PURPOSE: A lithium tantalate substrate is provided to prevent a comb pattern formed on a substrate from being broken and avoid damage to a lithium tantalate substrate by preventing sparks from being generated by a charge build-up on the substrate. CONSTITUTION: A lithium tantalate substrate has thermal strength of a heat treatment process in which lithium tantalate of an ingot state is buried in carbon powder or maintained in a carbon receptacle at a temperature from 650 deg.C to 1650 deg.C. The heat treatment process is continued for more than 4 hours. The lithium tantalate substrate is blackened by the heat treatment process.