中文摘要：

基于4H—SiC的材料特性，对具有双外延基区结构的4H—SiC双极晶体管进行研究．通过分析该结构在基区内部形成的自建电场以及基区渡越时间，利用正交试验的方法，基于各种器件二维模型，对该器件结构进行数值计算，并进行平均极差分析．计算结果表明，该器件的共发射结电流增益最高可达72，具有负温度系数，并且在一个很宽的集电极电流范围内该特性保持不变．

英文摘要：

With characteristics of 4H-SiC, a double base epilayer 4H-SiC bipolar junction transistors （BJTs） is investigated. By analyzing build-in electric field in the base region and the base transit time, the device is numerically calculated in two-dimensional models according to orthogonal experiments. A mean range analysis is made to find optimized structure of 4H-SiC BJTs. It shows that common emitter current gain with negative temperature coefficient is about 72 and it remains high in a wide range of collector current.