梯度掺杂纳米晶碳化硅/晶体碳化硅双缓变结的反向软恢复特性

项目名称： 梯度掺杂纳米晶碳化硅/晶体碳化硅双缓变结的反向软恢复特性

项目编号： No.61274006

项目类型： 面上项目

立项/批准年度： 2013

项目学科： 无线电电子学、电信技术

项目作者： 韦文生

作者单位： 温州大学

项目金额： 82万元

中文摘要： 半导体突变结快速恢复二极管(FRD)，反向恢复时因结区电荷难以控制而产生浪涌电流，影响了它在通信、高频电力电子设备中的应用。本项目拟在晶体碳化硅(c-SiC)二侧沉积梯度掺杂纳米晶碳化硅(nc-SiC)多层膜(ML)，构建(p+p-ML)nc-SiC/(n-)c-SiC/(nn+ -ML)nc-SiC双缓变结FRD。根据阳极发射率及少子寿命控制原理，模拟计算反向恢复时间、电流等参数，探究它们与不同结构及原子面SiC材料性质、双缓变结电学特性、低寿命少子控制区的位置及宽带、复合中心浓度及能级的关系。用PECVD在离子注入c-SiC两侧生长掺杂浓度递增的nc-SiC多层膜，形成双缓变结；再制备nc-SiC/nc-Si异质欧姆结与电极连接。表征双缓变结的结构、成份，分析电学性质，查明反向恢复特征，揭示导电机理。改进设计及工艺，实现超快反向软恢复，优化综合性能，为制造功率型电磁兼容器件提供思路。

中文关键词： 反向恢复二极管；纳米晶SiC/晶体SiC结；数值模拟；反向恢复参数测量；

英文摘要： The fast recovery diode (FRD) with a semiconductor abrupt junction would easily yield surge currents in the reverse recovery operating, which will be limited to apply in the communication equipments, high frequency power electronic systems, and so on. In this project, a kind of double graded junction (DGJ) with progressive doped nano-crystalline silicon carbide (nc-SiC) multi-layers deposited on two sides of a crystalline silicon carbide (SiC) wafer, is proposed to construct a (p+p ML)nc-SiC/(n-)c-SiC/(nn+ ML)nc-SiC FRD of DGJ. According to the controll principles of emitter efficiency and lifetime of minority carrers, via numerical calculating the parameters such as reverse recovery currents and time, etc, the relation between inverse recovery properties and SiC material parameters, electronic characteristics of DGJ, concentrations and locations of defect recombination centers,etc will be clarified. Further, using the plasma enhanced chemical vapor deposition (PECVD) technique, the p type and n type multi-layers of progressive increase doped nc-SiC films will be deposited respectively on both sides of c-SiC implanted by ions to form the (p+p ML)nc-SiC/(n-)c-SiC/(nn+ ML)nc-SiC DGJ. Subsequently, with the same method,the p+ type and n+ type nano-crystalline Si (nc-Si) films will be separately grown on the same ty

英文关键词： Reverse recovery diode；Nanocrystalline-SiC/crystalline-SiC junction；Numerical simulation；Reverse recovery parameter measurement；