[19p-Z25-1~14] 13.7 Compound and power electron devices and process technology

△ [19p-Z25-5] Fabrication and characterization of AlGaN channel HFETs with selective-area regrowth ohmic contacts

〇Akiyoshi Inoue¹, Hiroki Harada¹, Mizuki Yamanaka¹, Takashi Egawa¹, Makoto Miyoshi¹ (1.Nagoya Inst. Tech)

Keywords:Group-III nitrides, AlGaN-channel HFET, High breakdown voltage

Al_0.19Ga_0.81N-channel metal-insulator-semiconductor (MIS) HFETs employing a quaternary AlGaInN barrier layer and a selectively regrown n⁺-GaN contact layer were fabricated. The ohmic contacts were formed via the self-alignment selective-area growth (SAG) process consisting of the local-area recess etching and subsequent refilling process with a highly-Si-doped n⁺-GaN layer by metalorganic chemical vapor deposition (MOCVD). The fabricated MIS-HFETs exhibited good pinch-off characteristics with highly improved on-state performance. Furthermore, the fabricated devices also show a high off-state breakdown voltage of 1220 V at a gate-to-drain length of 10 μm.