On the Temperature Coefficient of 4H-SiC npn Transistor Current Gain

摘要

The temperature coefficient of 4H-SiC NPN BJT current gain is investigated by way of two-dimensional numerical simulations in this paper. Both positive and negative temperature coefficients in current gain can occur in 4H-SiC NPN BJT with Aluminum-doped base. 4H-SiC NPN BJTs would generally have a positive temperature coefficient if an acceptor with ionization energy level (E_A) smaller than 170meV were used. High base doping concentration is required to obtain negative temperature coefficient when carrier lifetime is low.