Controlled fracture of nonmetallic thin wafers using a laser thermal shock method

We developed a theoretical model of a novel thermal laser shock method for separation of glass and glass-ceramic wafers into chips. The suggested model allowed us to determine the operating parameters of the device for wafer splitting. The investigated method involves two stages: 1) formation of a surface (blind) microcrack (or a grid of surface microcracks) using a double thermal shock method, and 2) splitting the cracked wafer into chips along the microcrack contour by applying small bending stresses. The emphasis was given to splitting of thin wafers with the thickness less than 1 mm. The latter process is more involved because of the undesirable spontaneous transition of a surface microcrack into a through crack.