Patent ID: 7297972

Claim:
A system for processing structures on or within a semiconductor substrate using a pulsed laser, the system comprising: a laser source producing a pulsed processing laser beam for impinging upon selected ones of said structures as well as a metrology laser beam; a metrology laser propagation path from the laser source to a metrology laser beam spot on or within the semiconductor substrate, along which the metrology laser beam propagates; a processing laser propagation path from the laser source to a processing laser beam spot on or within the semiconductor substrate, along which pulses of the processing laser beam propagate; a motion stage configured to cause relative motion between the semiconductor substrate and both the metrology laser beam spot and the processing laser beam spot such that the processing laser beam spot intersects said selected ones of said structures, said motion being in a substantially straight direction; a sensor positioned to detect a magnitude of reflection of the metrology laser beam spot from one or more of said structures as the metrology laser beam spot moves relative to the semiconductor substrate, thereby generating a reflection signal; and a controller, connected to the sensor, configured to determine, based on the reflection signal, when or where to generate a pulse of the processing laser beam so as to impinge upon said selected ones of said structures.