High performance E-mode NiO/β-Ga2O3 HJ-FET with high conduction band offset and thin recessed channel

Abstract

In this paper, an enhancement-mode (E-mode) NiO/β-Ga2O3 heterojunction field-effect transistor (HJ-FET) with high conduction band offset (ΔEC) and thin recessed channel is proposed and studied by Sentaurus TCAD. Different from the existing HJ-FET with low ΔEC alignment, the High ΔEC HJ-FET can achieve a much lower on-resistance (Ron) due to the strong electron confinement effect. More importantly, the disadvantage in the threshold voltage (Vth) is compensated by reducing the thickness of the recessed channel, maintaining an almost unchanged Ron with the help of the special surface conduction channel. Compared with the corresponding Low ΔEC HJ-FET, at the same Vth (∼ 0.82 V), the Ron is decreased from 135 Ω/mm to 90.7 Ω/mm and the maximum drain current is increased from 14.9 mA/mm to 83.1 mA/mm. By adding a top p-NiO layer for further optimization, a greatly improved power figure of merit (P-FOM) of 2.29 GW/cm2 is achieved among the E-mode HJ-FETs. These results show that the proposed High ΔEC HJ-FET with thin recessed channel is probably a better choice to achieve the high-performance E-mode lateral HJ-FET.