MONTE-CARLO CALCULATIONS OF THE TEMPERATURE-DEPENDENT AND FIELD-DEPENDENT ELECTRON-TRANSPORT PARAMETERS FOR 4H-SIC

Monte Carlo simulation results for the field- and temperature-dependent electronic mobilities, drift velocities, and diffusion coefficients in 4H-SiC are presented. The calculations include crystal anisotropy, and values are obtained for field orientations both parallel and transverse to the c axis of the hexagonal structures. The simulations are based on electron effective mass data that has only recently become available. Our theoretical predictions of the electron mobilities and their anisotropy ratios compare very well with available experimental data at 300 K. A room-temperature velocity of 2.7x10(7) cm/s was obtained in 4H-SiC for transport parallel to the c axis. This value is found to be larger than both 6H and 3C material. Finally, our calculations for the longitudinal and transverse diffusion coefficients at 300 K indicate that both have appreciable field dependences and exhibit a ''soft'' threshold. (C) 1995 American Institute of Physics.