混合P-i-N和异质结二极管的设计与仿真  

Design and Simulation of Merged P-i-N and Heterojunction Diode

作　　者：王赫余 王颖[1] 

机构地区：[1]哈尔滨工程大学信息与通信工程学院

出　　处：《固体电子学研究与进展》2017年第3期172-175,181,共5页Research & Progress of SSE

基　　金：国家自然科学基金资助项目(51371063)

摘　　要：设计了一个混合P-i-N和多晶硅/4H-SiC异质结的二极管结构(MPH diode)。当正向偏置时,异质结区在低电压下开启,随着正偏电压的不断加大,P^+4H-SiC区域注入少数载流子到漂移区,在异质结下就会有明显的电导调制效应。异质结部分的正向传导增强,即使在高电流密度时,大多数的电流运输也会通过异质结区,这样会使得正向压降和储存电荷之间有一个很好的折衷。当反向偏置时,沟槽MOS结构形成夹断,从而使器件有低漏电流密度和高阻断电压。采用仿真工具Silvaco TCAD来研究MPH二极管的电学特性。结果表明,MPH二极管有低正向开启电压(0.8V),而且当正向电压大于2.7V时,P-i-N区域导通,正向电流密度快速增大。与MPS二极管相比,MPH二极管同样可以工作在高压状态下(2 332V),并且有较小的反向漏电流和较好的反向恢复特性。A merged P-i-N and heterojunction diode was designed.When forward biased,the heterojunction region conduction needs a small anode voltage.With the increasing forward bias,P~＋4H-SiC region minority carriers inject to drift region,which leads to obvious conductivity modulation effect.Due to the enhancement of forward conduction in heterojunction region,most of the current flow the heterojunction region even at high current density.There is a good compromise between forward drop and storage charge.When reverse biased,trench MOS structure is pinched off,so that the device has low leakage current density and high blocking voltage.The electrical characteristics of the MPH diode are studied by Silvaco TCAD simulation.The results show that the MPH diode has a low forward voltage drop（0.8V）,and when the forward voltage is greater than 2.7V,the P-i-N turns on,leading to the rapid increase of forward current.Compared with MPS diode,MPH diode can also work under high voltage condition（2 332V）with smaller reverse leakage current and better reverse recovery characteristic.

关 键 词：异质结 碳化硅 P-I-N二极管 反向恢复 高频 

分 类 号：TN386.2[电子电信—物理电子学]