METHOD AND MACHINE FOR CUTTING WAFER

摘要

PROBLEM TO BE SOLVED: To cut even a warped wafer at high speed with a desired quality by controlling the position of at least one of a laser irradiation means or a wafer based on a measurement of warp of the wafer such that a desired distance can be set between the wafer and the laser irradiation means. SOLUTION: A data is inputted from a laser distance meter 5 to a control means and a Z table 8 is shifted to set a desired distance a wafer 1 and an objective lens 7. An XY table 3A is then moved to attain a desired track while irradiating laser light 9. After cutting one chip, next chip is shifted to a cutting position and the distance to the wafer 1 is measured again by means of the laser distance meter 5 before the chip is cut again. Since the wafer is cut such that a constant distance is sustained between a laser irradiating means 6 and the surface of the wafer 1, focal point of laser light 9 is settled increase of splash or defective cutting due to warp is eliminated.