High performance CSTBT with p-type buried layer
A novel high performance carrier stored trench bipolar transistor (CSTBT) with a p-type buried layer (PBL-CSTBT) is proposed. The p-type layer of the structure is formed by ion implantation at the bottom of the trench after a partial etching of the Pbase/Ncs layer and the fabrication process is fully compatible with the conventional CSTBT (C-CSTBT) structure. In comparison with the C-CSTBT without a buried layer, the novel structure offers not only high breakdown voltage, but also improved Eoff-Vce(on) trade-off characteristics.