Abstract: A method of protecting and cleaning a semiconductor wafer using laser ablation includes the following steps: applies a protective coating on the side to be cut of a wafer with sapphire substrate, mounts the other side of the sapphire wafer on an adhesive tape, mounts the sapphire wafer on a cutting table, cuts the sapphire wafer with a laser, breaks the sapphire wafer into die, and cleans the sapphire wafer with a cleaning solution that removes slag resulting from the cutting, debris resulting from the breaking, and the protective coating, but the adhesive tape, the cleaning solution, and the protective coating are selected such that the cleaning solution does not damage the adhesive tape.

Abstract: A method for separating a semiconductor wafer into several thousand devices or dies by laser ablation. Semiconductor wafers are initially pre-processed to create multiple devices, such as blue LEDs, on the wafers. The wafers are then mounted with tape coated with a generally high level adhesive. The mounted wafer is then placed on a vacuum chuck (which is itself positioned on a computer controlled positioning table) to hold it in place during the cutting process. The cutting surface is then covered with a protective layer to prevent contamination from the effluent resulting from the actual cutting process. A laser beam is generated and passed through optical elements and masks to create a pattern, such as a line or multiple lines. The patterned laser projection is directed at the wafer at a substantially normal angle and applied to the wafer until at least a partial cut is achieved through it.