An implanted-emitter 4H-SiC bipolar transistor with high current gain

An epi-base, implanted-emitter, npn bipolar transistor which showed a maximum common emitter current gain (/spl beta/) of /spl sim/40, the highest current gain reported for BJT in any polytype of SiC has been experimentally demonstrated in 4H-SiC. The forward drop was /spl sim/1 V at forward current density of 50 A/cm/sup 2/. The current gain decreases hence specific on-resistance increases with increasing temperature. The negative temperature coefficient of /spl beta/ makes the device attractive for paralleling and for preventing thermal runaways.