The passivation mechanism of nitrogen ions on the gate leakage current of HfO_2/AlGaN/GaN MOS-HEMTs  

作　　者：BI ZhiWei HAO Yue FENG Qian JIANG TingTing CAO YanRong ZHANG JinCheng MAO Wei LU Ling ZHANG Yue 

机构地区：[1]Key Laboratory of Wide Band-Gap Semiconductor Materials and Devices, School of Microelectronics, Xidian University, Xi＇an 710071, China [2]State Key Laboratory of ASIC and System, School of Microelectronics, Fudan University, Shanghai 200433, China [3]School of Electronical ＆ Mechanical Engineering, Xidian University, Xi＇an 710071, China

出　　处：《Science China(Physics,Mechanics & Astronomy)》2011年第12期2170-2173,共4页中国科学：物理学、力学、天文学（英文版）

基　　金：supported by the National Natural Science Foundation of China (Grant Nos.60736033,60890191);the Fundamental Research Funds for the Central Universities (Grant Nos.JY10000925002,JY10000-904009)

摘　　要：In this paper, we systematically study the positive gate leakage current in AlGaN/GaN metal-oxide-semiconductor high electron-mobility transistors (MOS-HEMTs) with HfO 2 dielectric using atomic layer deposition (ALD). We observe that the incorporated nitrogen ions will improve the positive gate leakage current of devices obviously, but do not change the reverse gate leakage current. The passivation mechanism of nitrogen ions in oxygen vacancies in HfO 2 is studied by first-principles calculations. It is shown that the gap states of HfO 2 caused by oxygen vacancies increase the positive gate leakage current of MOS-HEMTs. Nitrogen ions passivate the gap states of HfO 2 and decrease the positive gate leakage current but do not effect the reverse gate leakage current.In this paper, we systematically study the positive gate leakage current in AlGaN/GaN metal-oxide-semiconductor high electron-mobility transistors （MOS-HEMTs） with HfO 2 dielectric using atomic layer deposition （ALD）. We observe that the incorporated nitrogen ions will improve the positive gate leakage current of devices obviously, but do not change the reverse gate leakage current. The passivation mechanism of nitrogen ions in oxygen vacancies in HfO 2 is studied by first-principles calculations. It is shown that the gap states of HfO 2 caused by oxygen vacancies increase the positive gate leakage current of MOS-HEMTs. Nitrogen ions passivate the gap states of HfO 2 and decrease the positive gate leakage current but do not effect the reverse gate leakage current.

关 键 词：ALGAN/GAN MOS-HEMT PASSIVATION gate leakage current nitrogen ions 

分 类 号：TN386[电子电信—物理电子学] TM862[电气工程—高电压与绝缘技术]