High Performance of Polysilicon/4H-SiC Dual-Heterojunction Trench Diode

A dual-heterojunction-trench (DHT) diode is proposed as having an improved electrical performance compared with dual-metal-trench (DMT) diodes. This paper is based on simulations performed using the Silvaco TCAD tool. The DHT diode not only improves the compromise between forward current and breakdown voltage but also has a better I-V characteristic compared with DMT diodes. The P-polysilicon region concentration was found to have only a minor effect but the mesa width, P
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polysilicon region concentration and drift region concentration have a great influence on the I-V characteristics of the proposed device. The effect of the interface charge and the forward and reverse characteristics of the proposed device at room and high temperatures were also simulated.