摘要
陷阱效应导致的电流崩塌是制约GaN基微波功率电子器件性能提高的一个重要因素,研究深能级陷阱行为对材料生长和器件开发具有非常重要的意义.随着器件频率的提升,器件尺寸不断缩小,对小尺寸器件中深能级陷阱的表征变得越发困难.本文制备了超短栅长(Lg=80 nm)的AlGaN/GaN金属氧化物半导体高电子迁移率晶体管(MOSHEMT),并基于脉冲I-V测试和二维数值瞬态仿真对器件的动态特性进行了深入研究,分析了深能级陷阱对AlGaN/GaN MOSHEMT器件动态特性的影响以及相关陷阱效应的内在物理机制.结果表明,AlGaN/GaN MOSHEMT器件的电流崩塌随着栅极静态偏置电压的增加呈非单调变化趋势,这是由栅漏电注入和热电子注入两种陷阱机制共同作用的结果.根据研究结果推断,可通过改善栅介质的质量以减小栅漏电或提高外延材料质量以减少缺陷密度等措施达到抑制陷阱效应的目的,从而进一步抑制电流崩塌.
Deep-level trapping effect is one of the most critical issues that restrict the performance improvement of Ga N-based microwave power devices. It is of very importance for material growth and device development to study the trapping behavior in the device. In the past decades, there have been made a lot of efforts to characterize and investigate the deep-level trapping phenomena. However, most of the previous researches focused on the large-scale devices. For pursuing higher frequency, the devices need to be scaled down. Consequently, it becomes more difficult to characterize the deep-level traps in small-scale Ga N-based devices, since none of the traditional characterization techniques such as capacitance-voltage（C-V） measurement and capacitance deep-level transient spectroscopy（C-DLTS） are applicable to small devices. Pulsed I-V measurement and transient simulation are useful techniques for analyzing trapping effects in Al Ga N/Ga N high electron mobility transitors（HEMTs）. In this work, Al Ga N/Ga N metal-oxide-semiconductor HEMTs（MOSHEMTs） with very short gate length（Lg = 80 nm） are fabricated. Based on the pulsed I-V measurement and twodimensional transient simulation, the influence of deep-level trap on the dynamic characteristic of short-gate Al Ga N/Ga N MOSHEMT is investigated. First, the pulsed I-V characteristics of Al Ga N/Ga N MOSHEMT with different quiescent bias voltages are studied. In addition, the current collapse induced by the trapping effect is extracted as a function of the quiescent bias voltage. Furthermore, the transient current of Al Ga N/Ga N MOSHEMT is simulated with the calibrated model, and the simulation exhibits a similar result to the measurement. Moreover, the physical mechanism of trapping effect in the device is analyzed based on the experimental data and simulation results. It is shown that the current collapse of Al Ga N/Ga N MOSHEMT varies non-monotonically with the increase of the gate quiescent bias voltage, which results from the combination effect of
作者
周幸叶
吕元杰
谭鑫
王元刚
宋旭波
何泽召
张志荣
刘庆彬
韩婷婷
房玉龙
冯志红
Zhou Xing-Ye;Lv Yuan-Jie;Tan Xin;Wang Yuan-Gang;Song Xu-Bo;He Ze-Zhao;Zhang Zhi-Rong;Liu Qing-Bin;Han Ting-Ting;Fang Yu-Long;Feng Zhi-Hong(National Key Laboratory of ASIC,Hebei Semiconductor Research Institute,Shijiazhuang 050051,China)
出处
《物理学报》
SCIE
EI
CAS
CSCD
北大核心
2018年第17期321-328,共8页
Acta Physica Sinica
基金
国家自然科学基金(批准号:61604137
61674130)资助的课题~~
关键词
氮化镓
高电子迁移率晶体管
动态特性
陷阱效应
GaN
high electron mobility transitors
dynamic characteristics
trapping effect
