A novel insulated gate technology for InGaAs high electron mobility transistors using silicon interlayer based passivation technique

A novel insulated gate technology for InGaAs high electron mobility transistors (HEMT) is described. It utilizes a silicon interface control layer (Si ICL)-based passivation structure. By applying an HF surface treatment, the technology becomes applicable to the air-exposed surfaces of InGaAs and InAlAs. The basic metal-insulator-semiconductor structures were fabricated and characterized in detail by x-ray photoelectron spectroscopy analysis and capacitance-voltage measurements. The interface has been shown to be essentially free from interface states. InGaAs insulated gate HEMTs (IGHEMT) were then successfully fabricated. The fabricated recessed gate IGHEMTs have good gate control of the drain current with good pinch-off characteristics. A highest effective mobility of 2010 cm(2)/Vs was obtained. The devices show extremely low gate leakage currents below 1nA/mm.