Method of forming a resist mask resistant to plasma etching.

摘要

A mask which is resistant to a plasma etching treatment is formed by lithographically patterning a radiation sensitive resist film (3) present on a substrate (1). The etch resistance of the mask is enhanced by exposure to a carbon monoxide plasma which forms a region (4) with an enhanced etch resistance at the surface of the patterned film. This method may be used for example to manufacture a photomask using a chromium coated glass substrate, or during the manufacture of semiconductor devices on a semiconductor wafer substrate (1).