Si-implanted InGaP/GaAs metal-semiconductor field-effect transistors

A new device structure for Si-implanted GaAs metal-semiconductor field-effect transistors (MESFETs), with an InGaP thin film on the GaAs surface, is proposed. A 200 Å InGaP film passivated the GaAs surface and increased the Schottky barrier height on n-type GaAs layers with a carrier concentration as high as 3×1018/cm3 to more than 0.6 eV. These effects persisted after annealing at 800 °C for 10 min. The transconductance of 2-μm-gate MESFETs remained above 150 mS/mm at gate voltages up to 1.0 V. Si-implanted InGaP/GaAs MESFETs are thus promising devices for use in high-speed and low-noise integrated circuits.