Scanning Capacitance Microscopy as a Characterization Tool for Semiconductor Devices

Abstract

Differences in dopant types and dopant concentrations in silicon were non-destructively imaged using a scanning capacitance microscope (SCM). Contrasts between regions with different dopant types, which could not be observed by atomic force microscope (AFM), were clearly observed. The contrasts visible in the SCM images taken at various dc bias voltages changed according to the dc bias applied to the sample with the ac modulation voltage. The dc bias dependence of the dC/dV signal (dC/dV - V) was also measured at three different locations selected on the SCM image.