| 摘要 |
An improvement is provided in the photolithographic patterning of a photoresist layer by pattern-wise exposure to short-wavelength ultraviolet light through a pattern-bearing photomask which is dustproof protected by mounting a framed pellicle thereon. With an object to overcome the troubles therein due to absorption of short-wavelength ultraviolet light by oxygen and the interaction of atmospheric oxygen in the space surrounded by the photomask and the framed pellicle with the energy of the short-wavelength ultraviolet, the framed pellicle is provided in the frame with at least two gas-passage openings through which the air inside is replaced with nitrogen in conducting the ultraviolet exposure. The openings are preferably covered with a filter member and covered further with a covering member having a gas nozzle which is connected to a feed source of an inert gas such as nitrogen. |
