界面处理对AlGaN/GaN MIS-HEMTs器件动态特性的影响

Impact of Interface Treatment on Dynamic Characteristic of AlGaN/GaN MIS-HEMTs

研究不同界面处理对AlGaN/GaN金属-绝缘层-半导体(MIS)结构的高电子迁移率晶体管(HEMT)器件性能的影响。采用N2和NH3等离子体对器件界面预处理,实验结果表明,N2等离子体预处理能够减小器件的电流崩塌,通过对N2等离子体预处理的时间优化,发现预处理时间10min能够较好地提高器件的动态特性,30min时动态性能下降。进一步引入AlN作为栅介质插入层并经过高温热退火后能够有效提高器件的动态性能,将器件的阈值回滞从411mV减小至111mV,动态测试表明,在900V关态应力下,器件的电流崩塌因子从42.04减小至4.76。

The effects of different kinds of interface treatment on the characteristic of AlGaN/GaN MIS-HEMTs were studied in this paper. N2 and NH 3 plasma pretreatment were used to improve the interface quality. The results show that N2 plasma pretreatment could reduce the current collapse of devices. By optimizing the time of N2 plasma pretreatment,it was found that the dynamic characteristic of devices with 10 min the pretreatment was improved,while that of 30 min was degraded. As a gate dielectric intercalation layer,the annealed AlN interlayer can effectively improve the dynamic characteristic of the device. The Vth hysteresis was decreased from 411 mV to 111 mV,and the device current collapse factor was reduced from 42.04 to 4.76 after under OFF-state VD stress of 900.