Gao Xiaohui, Guo Hui, Wang Rui, Pan Danfeng, Chen Peng, Chen Dunjun, Lu Hai, Zhang Rong, Zheng Youdou
Jiangsu Provincial Key Laboratory of Advanced Photonic and Electronic Materials, School of Electronic Science and Engineering, Nanjing University, Nanjing 210093, China.
Microfabrication and Integration Technology Center, Nanjing University, Nanjing 210023, China.
Micromachines (Basel). 2022 Aug 26;13(9):1396. doi: 10.3390/mi13091396.
In this paper, SiN film deposited by plasma-enhanced chemical vapor deposition was employed as a gate dielectric of AlGaN/GaN high electron mobility transistors (HEMTs). We found that the NH flow during the deposition of SiN can significantly affect the performances of metal-insulator-semiconductor (MIS) HEMTs. Compared to that without using NH flow, the device with the optimized NH flow exhibited three orders of magnitude lower gate leakage current, two orders of magnitude higher ON/OF drain current ratio, and an increased breakdown field by 69%. In addition, an in situ N plasma surface treatment prepared prior to SiN deposition can further improve DC performances of MIS-HEMTs to a very low gate leakage current of 10 mA/mm and a high ON/OFF drain current ratio up to 10 by reducing the interface state density. These results demonstrate the great potential for using PECVD-SiN as a gate dielectric in GaN-based MIS-HEMTs.
在本文中，采用等离子体增强化学气相沉积法沉积的氮化硅（SiN）薄膜作为氮化铝镓/氮化镓（AlGaN/GaN）高电子迁移率晶体管（HEMT）的栅极电介质。我们发现，氮化硅沉积过程中的NH流量会显著影响金属-绝缘体-半导体（MIS）HEMT的性能。与不使用NH流量的情况相比，具有优化NH流量的器件的栅极漏电流降低了三个数量级，开/关漏电流比提高了两个数量级，击穿场强增加了69%。此外，在氮化硅沉积之前进行的原位N等离子体表面处理可以通过降低界面态密度进一步将MIS-HEMT的直流性能提高到非常低的10 mA/mm栅极漏电流和高达10的高开/关漏电流比。这些结果证明了在基于氮化镓的MIS-HEMT中使用PECVD-SiN作为栅极电介质的巨大潜力。
