Study on High Quality Thermal Stress Cleavage of Thick Sapphire Wafer

Abstract

This study deals with high quality thermal stress cleavage of thick sapphire wafer with thickness of 5 mm. The influence of the distance from the edge to the initial crack, laser power, and plane orientation on the cleavage characteristics was experimentally investigated. The results indicate that the surface waviness Wa at the cleaved surface was influenced by the distance from the edge. A cleaved surface with good surface characteristics was obtained by cleaving with low laser power. The cleavage direction also affects the cleaved surface characteristics.