High Voltage, Low On-resistance 4H-SiC BJTs with Improved Junction Termination Extension

摘要

In this work, implantation-free 4H-SiC bipolar transistors with two-zone etched-JTE and improved surface passivation are fabricated. This design provides a stable open-base breakdown voltage of 2.8 kV which is about 75% of the parallel plane breakdown voltage. The small area devices shows a maximum dc current gain of 55 at Ic=0.33 A (J_C=825 A/cm2) and V_(CESAT)= 1.05 V at Ic = 0.107 A that corresponds to a low ON-resistance of 4 mΩ·cm~2 . The large area device shows a maximum dc current gain of 52 at Ic = 9.36 A (Jc=312 A/cm~2) and Vcesat = 1.14 V at Ic = 5 A that corresponds to an ON-resistance of 6.8 mΩ·cm~2. Also these devices demonstrate a negative temperature coefficient of the current gain (P=26 at 200℃) and positive temperature coefficient of the ON-resistance (R_(on) = 10.2 mΩ·cm ).