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.
出处
《电工技术学报》
EI
CSCD
北大核心
2015年第18期1-7,共7页
Transactions of China Electrotechnical Society
关键词
双基区结构
缓冲层
软恢复
二极管
Double-base region structure
buffer layer
soft recovery
diode
