A study on the automation of scanner matching

Scanner matching based on CD or patterning contours has been demonstrated in past works. All of these published works require extensive wafer metrology. In contrast, this work extends a previously proposed optical pattern matching method that requires little metrology by adding the component requirements and the procedure for creating an automation flow. In a test case, we matched an ASML XT:1900i using a DOE to an ASML NXT:1950i scanner using FlexRay. The matching was conducted on a 4x nm process test layer as a development vehicle for the 2x nm product nodes. The paper summarizes the before and after matching data and analysis, with future opportunities for improvements suggested.