Process technology and high temperature performance of 6H-SiC MOS devices

In this article, processing and characterization of 6H-SiC MOS devices is described. We start with gate controlled diode measurements determining the thermally grown oxide quality, describe the high temperature behavior of single enhancement-mode MOSFETs and present the static transfer characteristic of a monolithic differential amplifier. The gate oxides are investigated after five different contact anneal temperatures between 900°C and 1150°C. Contact annealing temperatures between 900°C and 1050°C cause only a slight increase in N_it from 1.0·10¹² cm^-2 to 1.6·10^-2 cm^-2. Leakage currents in the pre-tunneling region are very low and amount to about 4·10 ^-9 A/cm². Threshold implantations enable the realization of depletion- and enhancement-mode devices on the same wafer. This technology proves to be suited for the fabrication of integrated circuits