IEEE ELECTRON DEVICE LETTERS, cilt.39, ss.256-259, 2018 (SCI İndekslerine Giren Dergi)
We report on ultra-wide bandgap (UWBG) Al0.7Ga0.3N channel metal-oxide-semiconductor field-effect transistors (MOSFETs) grown by metal-organic chemical vapor deposition. Employing reverse Al composition graded ohmic contact layers and 20 nm Al2O3 gate-dielectric, 250 nm thick Al0.7Ga0.3N: Si channel MOSFETs resulted in the maximum current density of 0.5 A/mm, which is the highest value reported for AlGaN channels with Al composition >0.25. Transistors with a gate-drain spacing (LGD) of 1.7 mu m demonstrated a breakdown voltage (VDG) of similar to 620 V, translating in an average lateral breakdown field of similar to 3.6 MV/cm. This work establishes UWBG AlGaN as a promising candidate for advanced RF applications.