表面缺陷对SiC JBS二极管特性影响研究  

The Influence of Surface Defects on the Characteristics of SiC JBS Diodes

作　　者：胡继超 蒲红斌[1,2] 胡彦飞 陈治明[1,2] HU Ji-chao;PU Hong-bin;HU Yan-fei;CHEN Zhi-ming(Xi’an University of Technology,Xi'an 710048,China;不详)

机构地区：[1]西安理工大学,电子工程系,陕西西安710048 [2]西安市电力电子器件与高效电能变换重点实验室,陕西西安710048 [3]西安电子科技大学,微电子学院,陕西西安710071

出　　处：《电力电子技术》2020年第10期72-74,共3页Power Electronics

基　　金：国家自然科学基金(61904146);陕西省教育厅自然科学专项(18JK0585)。

摘　　要：由于碳化硅(SiC)外延材料中缺陷的影响,目前SiC结势垒肖特基(JBS)二极管实际性能仍低于理论预期。通过4H-SiC外延材料生长和表征、4H-SiC JBS二极管制作和器件特性测试分析,研究了表面缺陷对4H-SiC JBS二极管反向特性的影响。结果表明,当金属接触区或场限环区有彗星形缺陷或彗核存在时,器件击穿电压较低。胡萝卜缺陷会造成反向偏压较低时器件漏电流的增大,对器件的击穿电压影响不大。生长坑对器件的击穿电压和漏电流影响相对较小。三角形缺陷的存在会导致反向击穿电压降低约50%,漏电流增大4个数量级,对器件的反向特性有较严重的影响。分析认为,表面缺陷所导致的4H-SiC JBS二极管肖特基势垒高度的降低和缺陷处局部电场的增大是产生上述实验现象的主要原因。Due to the influence of defects in silicon carbide(SiC)epitaxial layers,the performance of SiC junction barrier Schottky(JBS)diodes still fall below theoretical expectations.4 H-SiC JBS diodes are fabricated and the electrical impacts of surface defects on the reverse characteristic of 4 H-SiC JBS diodes are investigated.It is found that comet causes premature breakdown and carrot degrades the leakage current at low reverse bias.Growth pits are harmless to device performance.A 50%reduction of breakdown and an increasement by four orders of magnitude of leakage current indicate that triangular defect influence characteristics of JBS diode seriously.According to the analysis,the reduction of Schottky barrier height and enhancement of local electric field are the main reasons for the influence of surface defects on the characteristics of 4 H-SiC JBS diode.

关 键 词：结势垒肖特基二极管 碳化硅 表面缺陷 

分 类 号：TN31[电子电信—物理电子学]