Novel structure of 4H-SiC bipolar junction transistor

A novel structure of 4H-SiC bipolar junction transistor (BJT) with floating buried layer (FBL) in the base epilayer is presented. Numerical simulations are performed to demonstrate that the current gain shows an approximately 100% increase due to the creation of buried layer electric-field. However, the variation rate of current gain is decreased sharply indicating FBL structure with high current gain stability due to reducing the recombination current of base-emitter depletion region. Furthermore, the charges in the buried layer modulate the electric-field resulting from a higher electric-field peak introduced at the etched edge of base-collector junction, which results in breakdown voltage (BV_CEO) enhanced.