Simultaneous Local Capacitance-Voltage Profiling and Deep Level Transient Spectroscopy Using Time-Resolved Scanning Nonlinear Dielectric Microscopy

Scanning nonlinear dielectric microscopy (SNDM) is a scanning probe technique that measures changes in oscillation frequency between the probe tip and a voltage-biased sample. As the probe moves across the surface of a semiconductor device, the oscillation frequency changes in response to variations in dielectric properties, charge and carrier density, dopant concentration, interface states, or any number of other variables that affect local capacitance. Over the past few years, researchers at Tohoku University have made several improvements in dielectric microscopy, the latest of which is a digital version called time-resolved SNDM (tr-SNDM). Here they describe their new technique and present an application in which it is used to acquire CV, dC/dV-V, and DLTS data from SiO2/SiC interface samples.