Self-consistent surface mobility and interface charge modeling in conjunction with experiment of 6H-SiC MOSFETs

Since an oxide can be grown on SiC it has great potential as a material on which MOS technology can be based. However, performance degradation of SiC enhancement mode MOSFETs due to poor quality SiC/SiO/sub 2/ interfaces continues to be a critical issue in the practical realization of SiC MOSFETs. In order to gain insight into the potential limitations of SiC MOSFET ICs, the degradation must be quantified. We develop a 2D, drift-diffusion based simulator specifically for SiC MOSFETs. We use the new simulator to extract internal details of the physical operation of SiC MOSFETs. By coordinating simulator development with experiment, we obtain a detailed SiC MOSFET mobility model, an interface state model, and an incomplete ionization model that yields agreement with experimental I-V curves. Included in our results is the extraction of an inversion layer saturation velocity that is approximately 20 times less than that of the bulk.