双基区结构快速软恢复二极管特性研究  

Investigation of the Characteristics of Fast Soft Recovery Diode with Double-Base Region Structure

作　　者：王建[1] 梁琳[1] 李有康 李晓明 余岳辉[1] 

机构地区：[1]华中科技大学光学与电子信息学院,武汉430074 [2]浙江正邦电力电子有限公司缙云,321400

出　　处：《电工技术学报》2015年第18期1-7,共7页Transactions of China Electrotechnical Society

摘　　要：为研究引入缓冲层的双基区结构对功率二极管反向恢复特性的改善作用,本文定量地讨论了缓冲层厚度和表面浓度对二极管的反向恢复时间、软度因子以及正向压降的影响。依据双基区结构设计须满足的条件,建立了双基区结构二极管模型,模型仿真结果表明缓冲层的厚度越小或者缓冲层表面浓度越高,二极管的软度因子越大,反向恢复时间越长,这是由缓冲层浓度梯度的影响引起的。结合具体工程项目的参数要求,即二极管反向恢复时间trr≤250ns,反向阻断电压VB≥1 000V,正向压降VF≤1V,给出了缓冲层厚度和表面浓度的最优值,即缓冲层厚度为70?m,表面浓度为1×1017cm?3。通过样品试制与特性检测实验,证明了双基区结构二极管的软恢复特性。In order to study the improvement of the double-base region structure with buffer layer on the power diode＇s reverse recovery characteristics, the influences of the buffer layer thickness and the surface concentration on the diode reverse recovery time, softness factor, and forward voltage drop are quantitatively discussed. The double-base region structure model satisfying the necessary conditions is established. The model simulation results show that the softness factor and the reverse recovery time can both be increased through decreasing the thickness or adding the surface concentration of the buffer layer, which is caused by the influence of the concentration gradient of the buffer layer. According to the project requirements, the reverse recovery time（trr） is less than 250 ns, the reverse blocking voltage（VB） is greater than 1 000 V and the forward voltage drop（VF） is less than 1V. The optimum buffer layer thickness and surface concentration level are 70μm and 1×10^17cm^-3, respectively. The soft recovery characteristics of the diode with the double-base region structure are demonstrated by prototyping and feature detection experiments.

关 键 词：双基区结构 缓冲层 软恢复 二极管 

分 类 号：TN312[电子电信—物理电子学]