InAlAs-InGaAs double-gate HEMTs on transferred substrate

We report the fabrication and the dc characterization of the first In/sub 0.52/Al/sub 0.48/As-In/sub 0.53/Ga/sub 0.47/As 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/sub d/ is 120 mA/mm, which gives a large ratio gm/I/sub d/ of 3.8 V/sup -/, indicating the improvement of the charge control efficiency due to the DG structure.