摘要 |
An integrated circuit is fabricated using photolithography by selectively exposing a photoresist layer to pattern a coarse line region of a wafer layer using a trim mask, and to pattern a fine line region of the wafer layer using an alternating phase-shift mask. The trim mask includes transparent, attenuated phase-shift and opaque regions. The phase-shifted attenuated light region patterns the coarse line region and the opaque region keeps light from exposing the fine line region. The alternating phase-shift mask patterns only the fine line region and includes one or more alternating phase-shift regions that each overlaps at least a portion of the opaque region but does not overlap the attenuated phase-shift region. The alternating phase-shift mask may be used to pattern the trim mask.
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