The enhanced voltage-dividing potentiometer for high-precision feature placement metrology

Enhancements to the voltage-dividing potentiometer, an electrical test structure for measuring the spatial separations of pairs of conducting features, are presented and discussed. These enhancements reduce or eliminate systematic errors which can otherwise lead to uncertainties as large as several hundred nanometers. These systematic errors, attributed by modeling to asymmetries at certain intersections of conducting features in the test structure, are eliminated by modifications to the test structure and test procedures.