[TuB4] High-Speed III-V Transistors

5:30 PM - 5:45 PM JST(8:30 AM - 8:45 AM UTC)

[TuB4-03] Thin-Barrier AlGaN/GaN HEMTs on 6-inch Si with PAE > 70% and Comparable Power Density for D-mode and E-mode Operations

〇Mengdi Li¹, Jiejie Zhu¹, Wanshuo Liao¹, Yifan Chen¹, Sheng Zhang², Ke Wei², Xinyu Liu², Xiaohua Ma¹, Yue Hao¹ (1. Xidian Univ. (China), 2. Inst. of Microelectronics, Chinese Academy of Sciences (China))

We fabricated high-performance depletion-mode (D-mode) and enhancement-mode (E-mode) thin-barrier AlGaN/GaN HEMTs on 6-inch Si substrates. High-strain LPCVD SiN passivation with regrown ohmic contacts reduces sheet and contact resistance. Employing BCl₃/Ar-based atomic layer etching enabled E-mode operation, yielding devices with no significant saturation current degradation. Load pull continuous-wave power characteristics measurement at 3.5 GHz shows >70% power-added-efficiency (PAE) for both D-mode (12-20 V) and E-mode (12-25 V) devices. At equal drain voltage (V_ds), the E-mode devices deliver maximum output power (P_out,max) comparable to the D-mode devices, with P_out,max of 4.21 and 4.36 W/mm for E-mode and D-mode devices respectively at V_ds = 20 V. Owing to its enhanced breakdown voltage, the E-mode devices achieve 6.54 W/mm P_out,max with 65.8% PAE at V_ds = 28 V. These results make D-mode and E-mode devices attractive for power electronics and RF applications, and pave the way for future monolithic integration of GaN-based E/D-mode devices.