High Frequency Inversion Capacitance Measurements for 6H-SiC n-MOS Capacitors from 450 to 600 °C

The operation of metal-oxide-semiconductor (MOS) devices based on the semiconductor SiC in high temperature environments above 300 °C requires an understanding of the physical processes in these capacitor structures under operating conditions. In this study we have focused on the regime of inversion biasing, where the electrical characteristics of the device are dominated by minority carriers. We report on the direct observation of the high frequency inversion capacitance due to thermal generation of holes in 6H-SiC n-MOS capacitors between 450 and 600 °C by monitoring the 1MHz C-V characteristics of large area, 1000 μm diameter, capacitors in the dark. Our experimental results are consistent with a first order calculation based on the delta depletion approximation.