Ultra-wide Bandgap AlGaN Channel HEMTs for Portable Power Electronics Applications

Abstract

AlGaN channel (Eg>3.4 eV) is the most effective method for enhancing the breakdown field of the group III-nitride based HEMTs. This work demonstrates the potential of AlGaN double channel HEMTs on Silicon carbide substrate. The device DC characteristics are investigated using numerical simulator by using drift-diffusion transport model. The AlGaN double channel HEMTs enhances the total 2DEG density due to double potential well and shows better current driving capability (IDS) of 0.714 A/mm, transconductance (gm) of 116 mS/mm, and low specific ON-resistance (Ron) of 3.262 Ω.mm. The AlGaN double channel HEMT on Silicon carbide substrate exhibited 680 V blocking voltage (VBR) and gate field plate HEMT shows 532 V. The effective reduction in electric field at the gate edge is the major source for elevated breakdown voltage in field plate HEMTs. The superior DC characteristics indicates the proposed wide bandgap channel HEMT is suitable device for future portable power converters.