将SiGeC技术应用于功率半导体器件的特性改进,提出了一种新型p^+(SiGeC)-n^--n^+异质结功率二极管结构.在分析SiGeC合金材料物理特性的基础上,给出了该结构的关键物理参数模型,并在此基础上利用MEDICI模拟,对比分析了C的引入对器件各种电特性的影响.此外,还模拟比较了不同p^+区厚度对器件反向漏电流的影响.结果表明:在SiGe/Si功率二极管中加入少量的C,在基本不影响器件正向I-V特性和反向恢复特性的前提下,大大减少了器件的反向漏电流,并且C的加入还减小了器件特性对材料临界厚度的依赖性,提高了器件稳定性.
A novel SiGeC/Si heterojunction structure for p-i-n power diodes is presented. Based on analysis of the physical characteristics of SiGeC alloys, models of the physical parameters are given, and the effects on the device characteristics of the incorporation of carbon are simulated and analyzed with MEDICI. The reverse leakage current is also compared for devices with different p+ region thicknesses. The simulation results indicate that the reverse leakage current and the dependence of the device characteristics on a critical thickness are reduced greatly,and the stability is improved by the incorporation of carbon atoms into SiGe/Si diodes,when the forward I-V and reverse recovery characteristics remain constant.