Analysis of a SCALPEL (TM) multi-pass writing strategy

In SCALPEL(TM). the microcircuit pattern information is written on the wafe r in a series of stripes, typically 2.75 mm wide with 0.24 mm pitch. To dis tribute the heat in the wafer as evenly as possible, each stripe may be wri tten with multiple passes of the sub-field illumination along each stripe, and a blending scheme will be used to improve the dose uniformity and reduc e CD errors near the boundaries at the ends and sides of each stripe. Our s oftware has been extended to simulate the performance of SCALPEL(TM) includ ing multi-pass writing strategies and blending regions. The method is descr ibed and illustrative results are presented. The results show that there is no significant loss of performance due to the multi-pass and blending sche mes.