SQUID DEVICE

• Main Authors: NAKATSU OSAMU, YOSHII MITSUYOSHI, KITA JUNICHI, YAMADA YASUHARU
• Format: Patent
• Language: English
• Published: 27.12.1991
• Subjects: BASIC ELECTRIC ELEMENTS; ELECTRIC SOLID STATE DEVICES NOT OTHERWISE PROVIDED FOR; ELECTRICITY; SEMICONDUCTOR DEVICES

PURPOSE:To prevent any noise and self heating from being produced by forming a metal film manifesting a proximity effect at the upper and lower stage sides putting a step provided on a substrate therebetween and further forming a high temperature superconductor thin film on the former, and constructing a Josephson junction part by joinning mutually weakly said films thorugh the stepped part. CONSTITUTION:A step part 1a is provided on the surface of a substrate 10 by etching using a resist film 11 as a mask, and an Au thin film is formed by sputtering, etc., from the upper portion. At this time, as the substrate 10 is slanted in the direction of the advance of sputtering particles, a stepped part 1a produces a shadow, and hence the Au thin film is not partly formed and the Au thin films separated mutually are formed. Then, a YBCO thin film 12 is uniformly formed by sputtering from the upper portion of the films 2, 3, and is weakly coupled on the upper and lower stage sides at the stepped part 1a. Then, there is formed a pattern by a resist 13 where the films 12 on the upper and lower stage sides are joinned at two portions along the stepped part 1a, which is used as a mask to etch the film 12 and hence a DC- SQUID device is yielded. Hereby, the noise is reduced and self heat production can be restricted.