Effect of defects in capacitance-voltage measurement of doping profiles in Ga2O3

We investigate the intermixing effects of doping profile and the carrier emission from deep levels in the capacitance-voltage measurement of the wide bandgap semiconductor material of 8-Ga2O3. Specifically, we find that the spatial non-uniformity of doping measured under practical conditions is substantially contributed by artifacts due to carrier emission from deep levels. We develop a procedure to measure the hysteresis in cyclic capacitance-voltage experiments in dark and at room temperature for probing of the deep levels contributing to the apparent doping profile. Analysis of this hysteresis in the dynamic electrostatic framework of a Schottky junction containing deep levels enables more accurate determination of the doping density and its spatial distribution, and simultaneously the extraction of energy, density, and capture cross-section of the deep levels.

Automated summary

We investigate the intermixing effects of doping profile and carrier emission from deep levels in the capacitance-voltage measurement of 8-Ga2O3 wide bandgap semiconductor material. We find that the non-uniformity of doping measured under practical conditions is mainly caused by artifacts due to carrier emission from deep levels. We develop a procedure to measure hysteresis in cyclic capacitance-voltage experiments for probing the deep levels contributing to the apparent doping profile. Analyzing this hysteresis enables more accurate determination of doping density and its spatial distribution, as well as extraction of energy, density, and capture cross-section of the deep levels.