Breakdown Voltage Enhancement of Al0.1Ga0.9 N Channel HEMT with Recessed Floating Field Plate

Abstract

In this paper, electrical and microwave characteristics of Al0.1Ga0.9N channel HEMTs was reported. The device performance were evaluated for conventional gate, field plate gate, and recessed floating field plate with Silicon nitride (SiN)/Hafnium oxide (HfO2) passivation. The recessed floating field plate HEMT with gate length LG = 0.8 µm, gate to drain distance LGD = 1 µm, and HfO2(SiN) passivation HEMT reports peak drain current density (IDS) of 0.282(0.288) A/mm at VGS = 0V, three terminal off-state breakdown voltage (VBR) of 677 (617) V, 6.38 Ω.mm of ON-resistance (RON), transconductance (gm,max) of 93( 95) mS/mm, and FT/FMAX of 11.4/49 (12/22) GHz. The HfO2 (SiN) passivation device demonstrated the Johnson figure of merit (JFoM)) of 7.71 (7.404) THz.V and FMAX x VBR product of 33.173 (13.574) THz.V. The high JFoM along with high FMAX x VBR indicates the potential of the ultrawide bandgap AlGaN HEMTs for future power switching and high-power microwave applications. The proposed device DC characteristics are validated with reported expeimental work, which shows similar IDS and 54% and and 31% improvement in breakdown voltage on comparisons with conventional HEMT.