| 摘要 |
PROBLEM TO BE SOLVED: To provide a method of preventing production of rotational asymmetrical aberration which occurs when rotational asymmetrical exposure is made, and of correcting exposure aberration with high accuracy in a stepper or a scanner. SOLUTION: In a first exposure process, Rebenson type phase shifter reticle, etc., is exposed, and a fine pattern is formed as a 'substrate'. Then, in a second exposure process, a pattern to form the profile of gate cells, etc., is exposed. After both patterns are superposed as an optical image, they are developed, and an arbitrary fine pattern is formed. In the first exposure process, a rotational asymmetrical pattern (exposure distribution) is formed on the lens near the pupil of a projective lens. In the second exposure process, a rotational symmetrical exposure distribution is formed. Then, the first and second exposure processes are repeated one after the other across reticle exchange, thus causing rotational asymmetrical exposure aberration to be alleviated, and only rotational symmetrical exposure aberration to be amplified.
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