| 摘要 |
<p>PROBLEM TO BE SOLVED: To obtain sufficient results by a multiple-focus exposure method with respect to most patterns except for a contact hole, by decomposing a whole pattern into a plurality of patterns in accordance with the local pattern shape and pattern density, and aligning and superimposing the decomposed patterns with each other to carry out exposure. SOLUTION: A whole pattern to be formed on a sensitive substrate includes a pattern PA bent at 90 deg. in a line-and-space(L/S) form and a simple L/S pattern PB, produced in a chip area CP. Each of the pattern PA and PB is divided into three decomposition patterns formed in three reticles R1 , R2 and R3 , respectively. The reticles R1 , R2 and R3 have a shading band SB on the circumferences thereof corresponding to a chip area CP. On the inner side of the shading band, patterns PTA1, PTA2 and PTA3 obtained by decomposing the pattern PA, and patterns PTB1, PTB2 and PTB3 obtained by decomposing the pattern PB are formed. After the patterns PTA1 and PTB1 are positioned and exposed to light in the chip area CP, the pattern PTA2 and PTB2 instead of the reticle C2 are positioned and exposed to light in the chip area CP. Then, the reticle R3 is positioned and the patterns PTA3 and PTB3 are exposed to light.</p> |
