New Method For BEOL Overlay And Process Margin Characterization


This paper presents a new method, design for inspection (DFI) to characterize overlay. Using design-assisted voltage contrast measurement, the method enables in-line test and monitoring of process induced OVL and CD variation of backend-of line (BEOL) features with litho-etch-lithoetch (LELE) patterning. While only some of the features of multi-color patterning scheme are chosen to be aligned d... » read more