Improved Off-State Leakage Current and Cutoff Frequency for AlGaN/GaN HEMT by Using Silicon-on-Insulator

Abstract

An improvement in off-state leakage current and cutoff frequency for AlGaN/GaN high electron mobility transistors (HEMTs) is investigated. Raman spectroscopy confirmed the low stress of GaN heterostructure grown on a silicon-on-insulator (SOI) substrate. The HEMT devices on SOI substrate showed lower knee voltage (Vknee) and on-resistance (RON) compared to those on the high-resistive silicon (HR-Si) substrates by 20.8% and 30.4%, respectively. Off-state leakage current was reduced to 10-7 A/mm, and the cutoff frequency (f_t) was increased by 19.2% as compared to HR-Si substrate. Thus, the GaN/SOI technology is proven to be a potential technology for high-frequency communication applications.