| 摘要 |
PURPOSE:To obtain the Josephson integrated circuit wherein the layout of a power source line and a signal line is easy, by dividing a first layer superconductive thin film into a plurality of parts, and using the main part as a ground plane and the other part as the power source line. CONSTITUTION:A thin Nb film 302 with a thickness of about 250nm is formed on the entire surface of an Si wafer 201 by a sputtering method. The pattern of the ground plane and the power source line is formed by an Al film 304 with a thickness of about 800nm. With this film as a mask, about 100nm of the thin Nb film of an insulating material forming part 303 is removed by sputter etching of Ar. Thereafter, the exposed thin Nb film is oxidized by anodic oxidation or the ion implantation of oxygen ions, and an Nb oxide (mainly Nb2O5) 402 is formed. In this method, an insulating material region 402 having an excellent width (about 20mum), which electrically separates the ground plane 202 and the power source line 203 can be formed. Since the volume is increased in the oxidation process, a planar structure can be simultaneously implemented. |
