GaAs metal–oxide–semiconductor field-effect transistor with nanometer-thin dielectric grown by atomic layer deposition

Abstract

A GaAs metal–oxide–semiconductor field-effect transistor(MOSFET) with thin Al 2 O 3 gate dielectric in nanometer (nm) range grown by atomic layer deposition is demonstrated. The nm-thin oxide layer with significant gate leakage current suppression is one of the key factors in downsizing field-effect transistors. A 1 μm gate-length depletion-mode n -channel GaAsMOSFET with an Al 2 O 3 gate oxide thickness of 8 nm, an equivalent SiO 2 thickness of ∼3 nm, shows a broad maximum transconductance of 120 mS/mm and a drain current of more than 400 mA/mm. The device shows a good linearity, low gate leakage current, and negligible hysteresis in drain current in a wide range of bias voltage.