中国物理B ›› 2015, Vol. 24 ›› Issue (2): 27302-027302.doi: 10.1088/1674-1056/24/2/027302
• CONDENSED MATTER: ELECTRONIC STRUCTURE, ELECTRICAL, MAGNETIC, AND OPTICAL PROPERTIES • 上一篇 下一篇
郑雪峰a b, 范爽a b, 陈永和a b, 康迪a b, 张建坤a b, 王冲a b, 默江辉c, 李亮c, 马晓华b, 张进成a b, 郝跃a b
Zheng Xue-Feng (郑雪峰)a b, Fan Shuang (范爽)a b, Chen Yong-He (陈永和)a b, Kang Di (康迪)a b, Zhang Jian-Kun (张建坤)a b, Wang Chong (王冲)a b, Mo Jiang-Hui (默江辉)c, Li Liang (李亮)c, Ma Xiao-Hua (马晓华)b, Zhang Jin-Cheng (张进成)a b, Hao Yue (郝跃)a b
摘要: The transport mechanism of reverse surface leakage current in the AlGaN/GaN high-electron mobility transistor (HEMT) becomes one of the most important reliability issues with the downscaling of feature size. In this paper, the research results show that the reverse surface leakage current in AlGaN/GaN HEMT with SiN passivation increases with the enhancement of temperature in the range from 298 K to 423 K. Three possible transport mechanisms are proposed and examined to explain the generation of reverse surface leakage current. By comparing the experimental data with the numerical transport models, it is found that neither Fowler-Nordheim tunneling nor Frenkel-Poole emission can describe the transport of reverse surface leakage current. However, good agreement is found between the experimental data and the two-dimensional variable range hopping (2D-VRH) model. Therefore, it is concluded that the reverse surface leakage current is dominated by the electron hopping through the surface states at the barrier layer. Moreover, the activation energy of surface leakage current is extracted, which is around 0.083 eV. Finally, the SiN passivated HEMT with a high Al composition and a thin AlGaN barrier layer is also studied. It is observed that 2D-VRH still dominates the reverse surface leakage current and the activation energy is around 0.10 eV, which demonstrates that the alteration of the AlGaN barrier layer does not affect the transport mechanism of reverse surface leakage current in this paper.
中图分类号: (III-V semiconductor-to-semiconductor contacts, p-n junctions, and heterojunctions)