Hole Generation Triggered Dynamic Drain Induced Barrier Lowering of RF GaN MIS-HEMTs

Hole Generation Triggered Dynamic Drain Induced Barrier Lowering of RF GaN MIS-HEMTs ■

Yi Yang, Yi Yang, Hao Yu, Hao Yu, Ying-Chun Kuo, Ying-Chun Kuo, Cheng Ying Huang, Cheng Ying Huang, Meng-Che Tsai, Meng-Che Tsai, Amratansh Gupta, Amratansh Gupta, Anna Navolotskaia, Anna Navolotskaia, Yiliang Chong, Yiliang Chong, Wei Tung Lin, Wei Tung Lin, Sachin Yadav, Sachin Yadav, Ali Reza Alian, Ali Reza Alian, Uthayasankaran Peralagu, Uthayasankaran Peralagu, Nadine Collaert, Nadine Collaert, Bertrand Parvais, Bertrand Parvais, Tian-Li Wu, Tian-Li Wu

Abstract ■

GaN RF MIS-HEMT, DIBL, hole trapping, free holesThis study investigates a strong negative threshold voltage (VTH) shift observed in short-channel RF GaN MIS-HEMTs caused by hole generation under high drain bias in the OFF-state. The VTH instability problem results in an abnormally large drain induced barrier lowering (DIBL) effect in DC measurement. We quantitatively distinguish two groups of holes that cause a negative VTH shift of RF GaN MIS-HEMT under high drain: we demonstrate that holes can not only get trapped by MIS-HEMT gate defects but also accumulate as free holes near the MIS-HEMT gate region under the large VDG stress. The results reveal that, beyond DIBL and hole trapping, accumulated free holes in the gate region also contribute significantly to the negative VTH shift under high drain bias.