Ga2O3 fin field-effect transistors with on-axis (100)-plane gate sidewalls fabricated on Ga2O3 (010) substrates

Abstract Ga 2 O 3 fin field-effect transistors (FinFETs) were fabricated on β -Ga 2 O 3 (010) substrates, which had on-axis (100)-plane gate sidewalls treated by nitrogen radical irradiation. The typical FinFET with a fin width ( W fin ) of 400 nm demonstrated decent on-state device characteristics such as a low specific on-resistance of 6.9 mΩcm 2 , a high drain current on/off ratio of over 10 9 , and a subthreshold slope of 82 mV/decade. The threshold voltage ( V th ) of the FinFETs increased with decreasing W fin , and enhancement-mode operation with V th > 0 V was achieved for W fin < 800 nm.