| 摘要 |
PURPOSE:To obtain a high-speed FET by forming a superlattice gate electrode having a potential period the same as or larger than that among the crystal lattice of a semiconductor substrate into a dielectric film on the main surface of the substrate between a source and a drain and superposing a second gate electrode, holding the dielectric film. CONSTITUTION:Superlattice gate electrodes 5 consisting of W, etc., and having width of 50-200Angstrom are shaped to a dielectric film 4 between n<+> type source-drain layers in a p-type Si substrate through a CVD method using ion beams, and a gate electrode 6 is superposed, holding the dielectric film 4. Since tunnel regions shaped under the gate electrodes 5 have a potential period of 50-200Angstrom in the FET, the mobility of carriers is increased extremely, and the effective mass of carriers is also reduced exceedingly. Accordingly, the same characteristics as excessively short gate length are displayed, and high-frequency characteristics are improved remarkably. |
