Comparing High Mobility InGaAs FETs with Si and GOI Devices

We demonstrate a dislocation-free InAlAs/InGaAs/InAlAs-on-Insulator (IIIVOI) HEMT on a Si substrate, which has a high drain current and 8,100 cm2/Vs mobility. To reduce the Schottky gate leakage current in the device, a high-κ Al2O3/InGaAs gate stack was used. By using this structure the gate leakage current was lower than that for a SiO2/Si MOSFET at the same equivalent-oxide-thickness (EOT), and the measured 451 cm2/Vs effective mobility was 2.5X higher.