Computational Process Control Compatible Dimensional Metrology Tool: Through-focus Scanning Optical Microscopy

Abstract

Using only two derived numbers based on a reference library, this paper shows how through-focus scanning optical microscopy (TSOM) is compatible with computational process control (CPC) for the complete 3Dshape process monitoring of nanoscale to microscale targets. This is demonstrated using three types of target switch widths (CDs) and depths ranging from 50 nm to1.0 μm, and 70 nm to 20 μm, respectively. TSOM is a high through put, low-cost and in-line capable optical dimensional metrology method ideally suited for high volume manufacturing (HVM), complementing other widely used metrology tools.