Electron transport in InAs field effect and mesoscopic devices

InAs based field effect devices with a low gate leakage current are reported. For the realization of gate controlled InAs mesoscopic devices, we fabricated and characterized InAs-channel heterostructure field effect transistors (HFETs) with an A1₂O₃ gate insulator in order to achieve the tunability of the electron density in the InAs channel. The maximum gate leakage current of less than 1 nA/mm at room temperature was achieved by inserting an A1₂O₃ gate insulating layer between the top GaSb layer and the gate metals. The maximum extrinsic transconductance of 1 μm gate HFET with a relatively thick A1₂O₃ of 80 nm was 180 mS/mm at V_D = 0.5 V. These devices show the successful modulation of the electron density, thus, the gate operation with a much reduced gate leakage current by using A1₂O₃ gate insulator.