InAlAs-InGaAs double-gate HEMTs on transferred substrate

We report the fabrication and the dc characterization of the first In_0.52Al_0.48As-In_0.53Ga_0.47As long double-gate (DG) high-electron mobility transistors (HEMTs). These devices have been obtained using a transferred substrate technique. Although the layer structure has not been optimized, a maximum extrinsic transconductance gm of 450 mS/mm is obtained. At the same bias voltage, the drain current I_d is 120 mA/mm, which gives a large ratio gm/I_d of 3.8 V^-, indicating the improvement of the charge control efficiency due to the DG structure.