SiC肖特基栅JFET功率特性的研究

提出了一种新型结构的SiC结型场效应晶体管,采用肖特基接触替代P+型栅区,以降低SiC JFET的工艺复杂度,并提高器件的功率特性。建立了器件的数值模型,对不同材料和结构参数下的功率特性进行了仿真。结果表明,与PN结栅相比,肖特基栅结构可以有效降低SiC JFET的开态电阻;与常规结构的双极模式SiC JFET相比,在SiC肖特基栅JFET的栅极正偏注入载流子,同样可以有效降低器件的开态电阻,折中器件的正反向特性,但不会延长开关时间。

Study on Power Characteristics of SiC Schottky Gate JFET

A novel structure of SiC junction field effect transistor(JFET) was proposed,in which Schottky contact,instead of P+-type gate,was used to reduce process complexity and improve performance of the device.Numerical model of the device was built,and power characteristics of SiC JFET with different structural parameters were simulated.It has been shown that,compared to PN junction gate,Schottky gate structure could effectively reduce on-state resistance of SiC JFET,and compared to bipolar-mode SiC JFET with conventional gate structure,injection of carriers into gate area of SiC Schottky-gate JFET at forward bias could also reduce its on-state resistance effectively,and make compromise between on-state and off-state characteristics,without increasing switching time.