LASER ALIGNMENT SYSTEM FOR PROCESSING SUBSTRATES

摘要

A laser alignment system includes a processing device that can direct a laser beam during a marking or scribing process of a substrate surface. Misalignment between the substrate and the processing device can be corrected by directly rotating the substrate by a rotating chuck (22) rather than lifting or reorienting the substrate using a robotic substrate handler (16), thus eliminating mechanical reorientation of the substrate. A sensing system (20) is used which includes a light source which illuminates the substrate edge. Light sensors, such as CCD sensors, positioned on an opposite side of the substrate can detect the substrate edge and so locate a reference flat or notch as the substrate is rotated.