据《IEEE Electron Device Letters》1992年第5期报道,美国霍华德大学首次采用V/Ti超导材料制作AlGaAs/GaAs HEMT栅电极,改进了器件的噪声性能。选择V/Ti超导材料是由于其超导转变温度为4.9K,高于4.2K,可以在液氦下观察。且其熔点比较低,为1903℃,制造较方便。超导HEMT的电极金属采用25nm的Ti,300nm的V/Ti和100nm的Au。而选用25nm的Ti According to “IEEE Electron Device Letters”, 1992, No. 5 reported that Howard University of the United States for the first time using V / Ti superconducting materials for AlGaAs / GaAs HEMT gate electrode to improve the noise performance of the device. Select V / Ti superconducting material is due to its superconducting transition temperature of 4.9K, higher than 4.2K, can be observed under liquid helium. And its relatively low melting point, 1903 ℃, more convenient to manufacture. The electrode metal of the superconducting HEMTs used Ti of 25 nm, V / Ti of 300 nm and Au of 100 nm. The choice of 25nm Ti