International Business Machines Corporation
Lithography process delay characterization and effective dose compensation

Abstract:

Techniques for lithography process delay characterization and effective dose compensation are provided. In one aspect, a method of analyzing a lithography process includes: applying a photoresist to a wafer; performing a post-apply bake of the photoresist; patterning the photoresist with sequences of open frame base line exposures performed at doses of from about 92% E0 to about 98% E0, and ranges therebetween, at multiple fields of the wafer separated by intervening programmed delay intervals, wherein E0 is the photoresist dose-to-clear; performing a post-exposure bake of the photoresist; developing the photoresist; performing a full wafer inspection to generate a grayscale map of the wafer; and analyzing the grayscale map to determine whether the intervening programmed delay intervals had an effect on the open frame base line exposures during the lithography process. Exposure dose compensation can then be applied to maintain a constant effective dose.