Terahertz detector using 70-nm T-gate InAlAs/InGaAs HEMT integrated with bow-tie antenna

A terahertz detector using an InAlAs/InGaAs high-electron-mobility-transistor (HEMT) integrated with a bow-tie antenna was proposed and fabricated. By utilizing ballistic transport in the short-channel, a current sensitivity of 1.5 A/W at 280 GHz was achieved by the detector having 70-nm T-gate HEMT without applying drain bias. We also measured the drain bias dependence of current sensitivity on the 50-nm-gate HEMT detector, and obtained a high current sensitivity of ~5 A/W at drain bias of >0.2 V.