| 摘要 |
<p>PURPOSE:To improve resolving power while ensuring focal depth by forming an optical attenuation pattern having amplitude transmittance within the range of a specific value to a mask and giving phase difference to other sections in the certain section of light passed through a pupil in a projection optical system. CONSTITUTION:An optical attenuation pattern is constituted so that amplitude transmittance is larger than 0% and smaller than 100% and phase difference in odd times as large as pi is not given between light passed through the pattern and light passed through other sections. A reticle 10 is used as a shifter-less halftone mask, and the amplitude transmittance of the section of a design pattern except the attenuation pattern is set in approximately 100% in the mask. The plane of optical incidence is formed in the doughnut shape of a plane in a filter 12a, and the filter 12a is designed so that phase difference at 180 deg. is generated between light passed through a zonal-shaped section and light passed through a circular notched section at a center.</p> |
