| 摘要 |
<p>A superconducting tunnel junction device comprises superconducting electrodes 11 and 12 separated by a tunnelling barrier 10 of semiconducting material.</p><p>According to the invention the tunnelling barrier is not uniform throughout its thickness, the middle portion 14 being treated to reduce the density of localized states, whereas the portions 15 adjacent to the superconducting electrodes are of untreated semiconductor. This enables a device of improved performance to be obtained.</p><p>In the preferred embodiment described in the specification the superconducting electrodes 11 and 12 are of niobium and the treated portion 14 of the barrier layer is of amorphous silicon containing hydrogen, the untreated portions 15 being of pure amorphous silicon. Various other superconducting materials for the electrodes and semiconductors for the barriers are mentioned, together with other gaseous additives. The devices may be manufactured by deposition steps in vacuum and in inert gas at low pressures.</p> |
