title: Gate leakage current induced trapping in AlGaN/GaN Schottky-gate HFETs and MISHFETs.
abstract: 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.
authors.affiliation: Department of Electrical Engineering, National Central University, No. 300, Jhongda Rd, Jhongli City, Taoyuan County 32001, Taiwan.
authors.forename: Wen-Chia
authors.initials: WC
authors.lastname: Liao
authors.affiliation: Department of Electrical Engineering, National Central University, No. 300, Jhongda Rd, Jhongli City, Taoyuan County 32001, Taiwan.
authors.forename: Yan-Lun
authors.initials: YL
authors.lastname: Chen
authors.affiliation: Department of Electrical Engineering, National Central University, No. 300, Jhongda Rd, Jhongli City, Taoyuan County 32001, Taiwan.
authors.forename: Zheng-Xing
authors.initials: ZX
authors.lastname: Chen
authors.affiliation: Department of Electrical Engineering, National Central University, No. 300, Jhongda Rd, Jhongli City, Taoyuan County 32001, Taiwan.
authors.forename: Jen-Inn
authors.initials: JI
authors.lastname: Chyi
authors.affiliation: Department of Electrical Engineering, National Central University, No. 300, Jhongda Rd, Jhongli City, Taoyuan County 32001, Taiwan.
authors.forename: Yue-Ming
authors.initials: YM
authors.lastname: Hsin
keywords: AlGaN/GaN heterostructure field-effect transistor (HFET); Dynamic on-resistance; Current collapse