MANUFACTURE OF CONNECTION TERMINAL OF SUPERCONDUCTIVE THIN FILM IC ELEMENT

PURPOSE:To avoid the generation of a contamination affected layer and thus obtain a stable superconductive characteristic by a method wherein, when forming the connection terminal of a Josephson junction element, superconductive metal with Nb as the main constituent is used for the terminal, and this surface is anodically oxidized. CONSTITUTION:An SiO2 film 22 is produced on an Si substrate 21, then a magnetic shielding film 23 constituted of Nb is adhered in a high vacuum at 10 Torr or less, and only the surface layer thereof is plasma-oxidized under O2 reduced pressure resulting in conversion into an NbO film 24. Next, the film 23 is photoetched and thus divided into a magnetic shielding film 23A, and external connection terminal, and an IC common earth terminal electrode 25, and accordingly an Nb2O3 film 26 due to the anodic oxidation is formed on the film 23A via the film 24. Thereafter, an SiO layer insulation film 27 is adhered thereon, then an Au-In lead resistor 28 is provided on a fixed region thereon, and it is surrounded by an SiO layer insulation film 29. Then, while filling between the shielding film 23A and the electrode 25, a Pb-In-Au internal wiring layer 30 is formed, and thus the resistor 28 is covered with the lower electrode 31 of the same material.