0.18 μm double-recessed III-nitride metal-oxide double heterostructure field-effect transistors

Weadopted a double-recess etching process and a new Digital-Oxide- Deposition (DOD) technique to fabricate 0.18 mum low-threshold AlInGaN/InGaN/GaN Metal- Oxide Semiconductor Double Heterostructure Field-Effect Transistors (MOS-DHFET). We for the first time report a high frequency operation of AlInGaN/InGaN/GaN MOS-DHFET. The gate- to-barrier aspect ratio is increased by the double recessed gate structure and the confinement of electrons is improved by a thin InGaN channel inserted between AlGaN barrier layer and GaN buffer. The ultra-thin gate oxide layer under the foot of the gate tremendously reduces the gate leakage and the drain leakage. We also compared the device performance of the InGaN channel MOS-DHFETs in Fig. 1 with that of the InGaN back-barrier MOS-DHFETs in Fig. 2.