Metal (CoSi2)/Insulator (CaF2) Hot Elelectron Transistor using Electron-Beam Lithography on Si Substrate

We fabricated small-area metal(CoSi2)/insulator(CaF2) hot electron transistor using electron-beam lithography. The transistor is composed of a CoSi2/CaF2 (1.9 nm)/CoSi2 (1.9 nm) tunnel emitter and a CaF2 (5 nm) collector barrier on n-Si(111) substrate. The emitter mesa area is 0.9×0.9 ¿m². Although the measured characteristics shows clear transistor action, collector current increases without sturation because of leakage current through SiO2 film under the outside electrode pads. The characteristics removed the leakage current exhibited the saturation, and current gain ß≫36 was obtained at 77K.