Noise Perfomance of Microwave HEMT

Low noise HEMTs (High Electron Mobility Transistors) with 0.5µm gate have been made using direct electron beam lithography. At 12 GHz a noise figure of 1.4 dB with an associated gain of 11 dB has been obtained at room temperature. Noise figure has been reduced to 0.35 dB by decreasing ambient temperature to 100K.