Patent ID: 6803161
Filing Date: 2004-10-12
Classification: G03F

Abstract:
A method for exposure of a photoresist layer on a substrate surface to ultraviolet light through a photomask, said method comprising:(A) mounting, on the photomask, a framed pellicle comprising, as an integral body, a pellicle frame made from a rigid material and having two parallel end surfaces, and a pellicle membrane made from a transparent plastic resin film spread over and adhesively bonded to one of the end surfaces of the pellicle frame in a slack-free fashion, the pellicle frame having at least two gas-passage openings each communicating the space surrounded by the pellicle membrane and the pellicle frame with the atmosphere outside of the pellicle frame; (B) filling the space surrounded by the photomask and the framed pellicle with a gas free from oxygen; (C) holding the photomask, with the framed pellicle supported thereon, on or above the substrate surface; (D) exposing the photoresist layer to ultraviolet light through the pellicle membrane and the photomask; and (E) covering at least one of the gas-passage openings with a covering member having a gas nozzle.