摘要 |
A contour of a mask design for an integrated circuit is modified to compensate for systematic variations arising from non-optical effects such as stress, well proximity, rapid thermal anneal, or spacer thickness. Electrical characteristics of a simulated integrated circuit chip fabricated using the mask design are extracted and compared to design specifications, and one or more edges of the contour are adjusted to reduce the systematic variation until the electrical characteristic is within specification. The particular electrical characteristic preferably depends on which layer is to be fabricated from the mask: on-current for a polysilicon; resistance for contact; resistance and capacitance for metal; current for active; and resistance for vias. For systematic threshold voltage variation, the contour is adjusted to match a gate length which corresponds to an on-current value according to pre-calculated curves for contour current and gate length at a nominal threshold voltage of the chip.
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