Patent ID: 6141081
Filing Date: 2000-10-31
Classification: G03F,H01S

Abstract:
A semiconductor wafer fabrication system comprising:a wafer exposing system which receives light generated by a laser, said exposing system providing optical elements between said laser and a mask, wherein said optical elements cause said light emitted by said laser to be attenuated prior to impinging upon said mask;a first light intensity detector positioned within said exposing system so as to receive at least a portion of laser light exiting at least one of said optical elements and prior to said light impinging upon said mask;a second light intensity detector positioned proximate to said laser so as to receive at least a portion of laser light output from said laser; anda processor connected to receive a first signal relating to an output of said first light intensity detector and a second signal relating to an output of said second light intensity detector, said processor analyzing said first signal and said second signal and controlling an exposure of a semiconductor wafer to laser light based upon a relationship of said first signal to said second signal.