METHOD AND SYSTEM FOR OPTIMIZING ALIGNMENT PERFORMANCE IN A FLEET OF EXPOSURE TOOLS

摘要

A method for optimizing alignment performance in a fleet of exposure systems involves characterizing each exposure system in a fle of exposure systems to generate a set of distinctive distortion profiles (301) associated with each exposure system The set of distinct distortion profiles are stored in a database (303) A wafer having reference pattern formed thereon is provided for further pattern fabpcation (305) and an exposure system is selected from the fleet to fabricate a next layer on the wafer (307) Linear and higher ord parameters of the selected exposure system are adjusted using the distinctive distortion profiles to model the distortion of the referen pattern (309) Once the exposure system is adjusted, it is used to form a lithographic pattern on the wafer (311).