MIS型GaN HEMT器件的X-ray辐射总剂量效应研究  

Study of X-ray Total-Ionizing-Dose Effect in MIS Type GaN HEMT Device

作　　者：吴素贞 徐政 徐海铭 宋思德 谢儒彬 洪根深 吴建伟 贺琪 WU Suzhen;XU Zheng;XU Haiming;SONG Side;XIE Rubin;HONG Genshen;WU Jianwei;HE Qi(China Key System&Integrated Circuit Co.,Ltd.,Wuxi 214072,China)

机构地区：[1]中科芯集成电路有限公司,江苏无锡214072

出　　处：《电子与封装》2020年第12期66-70,共5页Electronics & Packaging

摘　　要：通过对MIS型GaN HEMT器件在不同电偏置条件下进行X-ray辐射试验,研究了MIS型GaN阈值电压对辐射总剂量(TID)的响应规律,分析了绝缘栅介质/Al GaN叠层结构在500 krad总剂量过程中的电荷积累行为。结合辐射导致的空穴积累和外加偏压导致的电子/空穴积累,说明了MIS型GaN HEMT器件的阈值参数随总剂量变化的机制。在不加外加偏置电压辐射时,栅介质层/Al GaN层存在的空穴陷阱导致正电荷积累;在栅极正向偏置辐射下,栅极注入空穴,加速了空穴的积累,导致更大的阈值降低;而在栅极反向偏置辐射下,栅极注入电子过程与辐射电离产生的电子空穴输运、俘获过程相互耦合,导致非单调的阈值变化。研究结果对评价GaN功率器件空间应用可行性以及评价GaN器件栅极可靠性具有一定的指导意义。The X-ray total-ionizing-dose(TID)responses of MIS based GaN HEMTs under different bias conditions were studied,especially the shift phenomenon in threshold voltage parameter.The charge accumulation behavior in insulator/AlGaN stack layers was analyzed up to 500 krad TID.Combination of the external applied bias induced electron or hole trapping effect and the radiation induced hole trapping effectcan well explain the threshold voltage change with TID.The threshold voltage shows a negative reduction due to hole tapping during radiation without biasing,and shows a worse negative reduction with gate electrode forward biased.While for gate electrode reverse biasing condition during radiation,non-monotone variation occurs due to the interaction of bias induced electron trapping and radiation induced hole trapping.Above research results will have certain guiding significance for evaluating GaN power devices in space application and the reliability of GaN gate module.

关 键 词：GaN HEMT MIS栅结构 X-ray总剂量辐射效应 阈值电压 

分 类 号：TN306[电子电信—物理电子学]