Metal Etch Depth Metrology using YieldStar and CDSEM

Abstract

In this work we demonstrate and report the capability of YieldStar and CDSEM to measure etch depths of metal in a data-driven approach. We find that both Yieldstar and CDSEM enable recess depth measurements with a precision of 0.5 nm over a range of 17 nm. Combining YieldStar and CDSEM (hybrid metrology) further improved prediction errors by 0.1 nm.