MODELING AND CHARACTERIZATION OF THERMALLY OXIDIZED 6H SILICON-CARBIDE

Wet oxidation and computer simulation of metal oxide semiconductor (MO S) structures were studied on n-type (Si-face and C-face) and p-type ( Si-face) 6H-SiC. The effects of thermal oxidation conditions at temper atures between 1100 and 1250 degrees C on the electrical properties of MOS capacitors were studied. Oxidation model parameters for SSUPREM3 are presented, and simulation results are compared to laboratory studi es with good agreement. The C-V characteristics of the MOS capacitors were measured at high frequency in the dark and under illumination at room temperature. Samples gh prepared by wet oxidation showed accumula tion, depletion, and inversion regions, but they did not show inversio n regions under dark conditions. The interface trap densities and emis sion time constants of fast states were determined by ac conductance m easurements. The electrical properties of n- and p-type 6H-SiC were co mpared. It was found that oxidation rate of C-face was five to seven t imes faster than that of Si-face on n-type SiC. The electrical propert ies of Si-face and C-face of n-type 6H-SiC showed that the quality of oxide on the Si-face was superior to the oxide on the C-face.