摘要 |
An exposure mask having phase shifting films (3) of a predetermined thickness composed of a material transparent to the wavelength of exposure light and formed on a substrate (1) transparent to such wavelength for causing a desired phase shift, wherein the phase shifting films are so patterned as to have an arrangement of repeated patterns principally. Relative to the rule width L of the repeated patterns projected onto a work member to be exposed, a pattern having a rule width of 2L/m is formed, in which m (</= 1) is a size reduction magnification in the use of a reduced-size projection exposer. The exposure mask is adapted for use in producing a diffraction grating as well. The mask is easily manufacturable without the necessity of any intricate process such as a positioned exposure, hence minimizing the number of required steps in manufacture while achieving a further fine work with an enhanced resolution higher than the known value. |