Scanning nonlinear dielectric microscopy is continuously developed as an AFM-derived method for 2D dopant profiling of semiconductor devices. In this paper, the authors apply 2D carrier density mapping to Si and SiC and succeed a high resolution observation of the SiC planar power MOSFET. Furthermore, they develop software that combines dC/dV and dC/dz images and expresses both density and polarity in a single distribution image. The discussion provides the details of AFM experiments that were conducted using a Hitachi environmental control AFM5300E system. The results indicated that the carrier density decreases in the boundary region between n plus source and p body. The authors conclude that although the resolutions of dC/dV and dC/dz are estimated to be 20 nm or less and 30 nm or less, respectively, there is a possibility that the resolution can be further improved by using a sharpened probe.

Scanning nonlinear dielectric microscopy (SNDM) has improved significantly, achieving low-concentrated observations. Therefore, it is of great interest to observe how adsorbed water and other measurement environments influence SNDM measurements so that the material's dielectric properties can be detected. This study investigates how specific measurement environments, namely air, dry nitrogen, and vacuum environments, influence the SNDM and C-V curve measurements of semiconductor samples. The p-n structure created by ion implantation was measured by applied-DC-voltage SNDM, and in these environments, the corresponding C-V curves were obtained. As with the p-n structure sample, an abnormal result was obtained when a positive DC voltage was applied to an epi-Si sample in air. A low concentration level was clearly measured in vacuum. From these results, it can be concluded that measurement in a high vacuum is an effective way to obtain highly precise carrier distributions.