Liao Wen-Chia, Chen Yan-Lun, Chen Zheng-Xing, Chyi Jen-Inn, Hsin Yue-Ming
Department of Electrical Engineering, National Central University, No. 300, Jhongda Rd, Jhongli City, Taoyuan County 32001, Taiwan.
Nanoscale Res Lett. 2014 Sep 8;9(1):474. doi: 10.1186/1556-276X-9-474. eCollection 2014.
This study examined the correlation between the off-state leakage current and dynamic on-resistance (RON) transients in AlGaN/GaN heterostructure field-effect transistors (HFETs) with and without a gate insulator under various stress conditions. The RON transients in a Schottky-gate HFET (SGHFET) and metal-insulator-semiconductor HFET (MISHFET) were observed after applying various amounts of drain-source bias stress. The gate insulator in the MISHFET effectively reduced the electron injection from the gate, thereby mitigating the degradation in dynamic switching performance. However, at relaxation times exceeding 10 ms, additional detrapping occurred in both the SGHFET and MISHFET when the applied stress exceeded a critical voltage level, 50 V for the SGHFET and 60 V for MISHFET, resulting in resistive leakage current build-up and the formation of hot carriers. These high-energy carriers acted as ionized traps in the channel or buffer layers, which subsequently caused additional trapping and detrapping to occur in both HFETs during the dynamic switching test conducted.
本研究考察了在各种应力条件下，有无栅极绝缘体的AlGaN/GaN异质结构场效应晶体管（HFET）的关态漏电流与动态导通电阻（RON）瞬变之间的相关性。在施加不同量的漏源偏置应力后，观察到肖特基栅HFET（SGHFET）和金属绝缘体半导体HFET（MISHFET）中的RON瞬变。MISHFET中的栅极绝缘体有效地减少了从栅极注入的电子，从而减轻了动态开关性能的退化。然而，在弛豫时间超过10毫秒时，当施加的应力超过临界电压水平（SGHFET为50 V，MISHFET为60 V）时，SGHFET和MISHFET中都会发生额外的去俘获，导致电阻性漏电流积累和热载流子的形成。这些高能载流子在沟道或缓冲层中充当电离陷阱，随后在进行的动态开关测试期间，导致两个HFET中都发生额外的俘获和去俘获。
