| 摘要 |
PURPOSE:To increase the superconductive coherence distance and to enhance the sensitivity of a device by a method wherein the length in the transverse direction (the length in the direction perpendicular to the source-drain direction) of a channel which is caused on a heterojunction interface of a semiconductor is made shorter than a de Broglie wavelength of an electron system. CONSTITUTION:A first semiconductor thin film 5, a second semiconductor thin film 6 and a gate electrode 4 are formed in succession on a semiconductor substrate 1 to become a laminated structure; between a source and a drain, the length W in the transverse direction of this laminated structure is made shorter than a de Broglie wavelength of an electron system inside a channel. That is to say, the length W (line width) in the transverse direction of the channel is constructed to be shorter than the de Broglie wavelength. A source electrode 2 and a drain electrode 3, both composed of a superconductive metal, come into contact with a heterojunction interface in an ohmic way. Because, with this superconductive three-terminal device, the coherence distance becomes long, it is possible to shraply increase a maximum Josephson current and the sensitivity S per unit line width of the channel as compared with a conventional superconductive TFT. |
