METHOD AND SYSTEM FOR REPAIRING DEFECTED PHOTOMASKS

摘要

A system and method for repairing a photomask (52) for use in a photolithography process is disclosed, the photomask (52), consisting of a substrate layer (38) and a chrome layer (36) over the substrate layer (38), having a defect (42) in the chrome layer (36), the method comprising: providing a pulsed laser source (1) for generating an ultra-short pulsed laser beam; providing optical elements for scanning, directing and focusing the pulsed laser beam at a desired target location; directing the pulsed laser beam through the substrate and focusing it on a target location located inside the substrate adjacent the defect (42) to write a diffractive optical element (34), thus changing the scattering properties of the substrate at the target location.