Oxide superconductor and method for manufacturing the same

Patent metadata

Field	Value
Publication number	US-11335481-B2
Application number	US-202016863344-A
Country	US
Kind code	B2
Filing date	Apr 30, 2020
Priority date	Aug 10, 2016
Publication date	May 17, 2022
Grant date	May 17, 2022

Abstract

An oxide superconductor of an embodiment includes an oxide superconductor layer having a continuous Perovskite structure containing rare earth elements, barium (Ba), and copper (Cu). The rare earth elements contain a first element which is praseodymium (Pr), at least one second element selected from the group consisting of neodymium (Nd), samarium (Sm), europium (Eu), and gadolinium (Gd), at least one third element selected from the group consisting of yttrium (Y), terbium (Tb), dysprosium (Dy), and holmium (Ho), and at least one fourth element selected from the group consisting of erbium (Er), thulium (Tm), ytterbium (Yb), and lutetium (Lu).

First claim

What is claimed is:

1. A method for manufacturing an oxide superconductor, comprising:
preparing an aqueous solution including an acetate of a first element which is praseodymium (Pr), an acetate of at least one second element selected from the group consisting of neodymium (Nd), samarium (Sm), europium (Eu), and gadolinium (Gd), an acetate of at least one third element selected from the group consisting of yttrium (Y), terbium (Tb), dysprosium (Dy), and holmium (Ho), an acetate of at least one fourth element selected from the group consisting of erbium (Er), thulium (Tm), ytterbium (Yb), and lutetium (Lu), an acetate of barium (Ba), and an acetate of copper (Cu);
mixing the aqueous solution with a perfluorocarboxylic acid to prepare a mixed solution;
subjecting the mixed solution to a reaction and purification to prepare a first gel;
adding an alcohol including methanol to the first gel and dissolving the first gel therein to prepare an alcohol solution;
subjecting the alcohol solution to a reaction and purification to prepare a second gel;
adding an alcohol including methanol to the second gel and dissolving the second gel therein to prepare a coating solution in which a total weight of residual water and residual acetic acid is 2% by weight or less;
applying the coating solution on a substrate to form a gel film;
subjecting the gel film to calcining at 400° C. or lower to form a calcined film; and
subjecting the calcined film to firing under a humidified atmosphere at 725° C. or higher and 850° C. or lower and oxygen annealing to form an oxide superconductor layer.

2. The method according to claim 1 , wherein content by percentage of the trifluoroacetic acid in the perfluorocarboxylic acid is 98 mol % or more.

Assignees

• Toshiba Kk

Inventors

• Araki Takeshi
• Ishii Hirotaka
• Kobayashi Nao

Classifications

• C04B2235/656

  characterised by specific heating conditions during heat treatment · CPC title

• C23C18/1295

  with after-treatment of the deposited inorganic material · CPC title

• C04B2235/79

  Non-stoichiometric products, e.g. perovskites (ABO3) with an A/B-ratio other than 1 · CPC title

• C23C18/1216

  Metal oxides (C23C18/1212 takes precedence) · CPC title

• C04B2235/6584

  at an oxygen percentage below that of air · CPC title