Method of producing a phase shifting mask

摘要

A mask for use in an optical exposure apparatus with single wavelength light includes a light shielding film pattern having two spaced apart portions on a transparent substrate, a transparent thin film for shifting the phase of light transmitted through the mask disposed in the aperture between the light shielding film portions and spaced from the light shielding film portions. The resolution and contrast of the image of the pattern projected onto a wafer are enhanced and the resolution and depth of focus of the photoresist on which the pattern is projected are improved.