Patent ID: 6562549
Filing Date: 2003-05-13
Classification: G03F

Abstract:
A method for manufacturing a semiconductor comprising the steps of:interposing a finished photomask, having substantially transparent areas, between a semiconductor wafer and an energy source; transmitting energy generated by said energy source through said substantially transparent areas of said finished photomask to said semiconductor wafer; and etching an image, corresponding to said substantially transparent areas of said finished photomask, on said semiconductor wafer, wherein said finished photomask is created from an under processed photomask by a process for removing excess portions of opaque material from said under processed photomask thereby adjusting out of tolerance critical dimensions to within predetermined limits, said under processed photomask comprising a substantially transparent substrate and selected areas of opaque material and anti-reflective material covered by resist material, said anti-reflective material having an initial thickness with a reflectivity value reflecting a first percentage of incident energy, and said process of removing excess portions comprising the steps of: (a) removing said resist material; (b) measuring at least one critical dimension of said opaque material; (c) determining the amount of excess opaque material to be removed to bring said at least one critical dimension within predetermined limits; and (d) exposing said under processed photomask to electrified plasma gases for a period of time, said period of time corresponding to the desired amount of excess opaque material to be removed, said anti-reflective material after said exposure to electrified plasma gases having a second thickness with a reflectivity value reflecting a second percentage of incident energy less than a predetermined value that an imaging device can accommodate without adversely impacting its operation.