Comparative Monte Carlo study of electron transport in 3C, 4H and 6H silicon carbide

Temperature-and electric field-dependent electron transport in 3C, 4H, and 6H: SiC is studied by the Monte Carlo technique. Due to freeze-out of deep donor levels the role of ionized impurity scattering in 6H SiC is suppressed as compared to 4H SiC. There are in dications of impurity band formation for impurity concentrations exceeding 10(19) cm(-3) in 6H polytype. Electron effective masses and electron-phonon coupling constants are deduced by fitting the electron mobilities obtained by the Monte Carlo simulations to the available experimental data. The extracted model parameters are used for high-field electron transport; simulations. The calculated velocity-field dependences agree with experimental results.