SiC基反向开关晶体管RSD关键工艺概述  

Key process summary of SiC-based reversely switched dynistor(RSD)

作　　者：梁琳[1] 吴文杰[1] 刘程[1] 潘铭[1] 

机构地区：[1]华中科技大学光学与电子信息学院,湖北武汉430074

出　　处：《电工电能新技术》2016年第4期56-60,共5页Advanced Technology of Electrical Engineering and Energy

基　　金：国家自然科学基金(51377069);台达环境与教育基金会<电力电子科教发展计划>(DREG2013004);中国工程物理研究院脉冲功率科学与技术重点实验室基金(PPLF2013PZ02);中国国家留学基金委(201308420123)资助项目

摘　　要：本文首次概述了采用宽禁带半导体材料4H-SiC制备脉冲功率开关反向开关晶体管(RSD)所涉及到的关键工艺。包括选择性刻蚀、选择性掺杂、欧姆电极制备以及台面终端造型等在内的多步主要工艺均与Si基RSD完全不同,采用氟基气体感应耦合等离子体(ICP)刻蚀得到了合适的刻蚀速率、表面粗糙度及形貌,采用多次氮离子注入及高温退火完成选择性掺杂,采用Ni/Ti/Al多层金属配合适当退火温度完成欧姆电极制备,采用机械切割斜角完成台面终端造型,最终得到了合理的器件正反向阻断特性。The key processes related to fabrication of the pulsed power switch RSD（ reversely switched dynistor）with the wide bandgap semiconductor material 4H-SiC are summarized in this paper firstly. Multiple key processes including selective etching,selective doping,ohmic contact electrode fabrication and bevel edge termination are totally different from those of Si-based RSD. The selective etching is carried out by the ICP（ inductively coupled plasma） etching with fluoro-based gas. Proper etch rate,surface roughness and morphology are acquired in experiments. The selective doping is carried out by the multiple nitrogen ions implantation and high temperature annealing. The Ni / Ti / Al metal with proper annealing temperature is used to fabricate the ohmic contact electrodes,in which the specific contact resistances for both P and N type SiC are considered. The bevel dicing with etching treatment is used to make the junction termination,which is still a new and special process for Si C power devices. Reasonable forward and reverse blocking characteristics are acquired finally.

关 键 词：SIC RSD 脉冲功率开关 工艺 ICP刻蚀 离子注入 台面终端造型 

分 类 号：TN34[电子电信—物理电子学]