| 摘要 |
PURPOSE:To make the interface between an electrode and a layer serving as the tunnel barrier as a layer of good quality without the mixing-in of impurities, the disorder in crystal arrangement, etc. by a method wherein the surface of a superconductive thin film having good characteristics in the latter period of growth is put into direct contact with a layer having the tunnel barrier. CONSTITUTION:The second substrate S2 made of a superconductive substance and a heat-resistant material having etching selectivity is prepared. Then, superconductive layers, e.g., niobium layers 6a and 6b are grown on an SiO insulation film 4 and the second substrate. The surfaces of the layers come into the state of layers of good characteristics without the mix-in of impurities or the disorder in crystallinity. Thin aluminum films 7a and 7b are adhered thereon. Further, aluminum oxide films 8a and 8b serving as the tunnel barrier are grown thereon. Next, the substrates S1 and S2 are superposed in opposition to each other on surfaces, i.e., on the surfaces of the films 8a and 8b, and then pressure-bonded by heating in vacuum. Besides, the substrate 5 is removed with O2 plasma, and then the element is obtained by patterning. |
