Methods for treating superconducting cavities

Patent metadata

Field	Value
Publication number	US-11266005-B2
Application number	US-202016784092-A
Country	US
Kind code	B2
Filing date	Feb 6, 2020
Priority date	Feb 7, 2019
Publication date	Mar 1, 2022
Grant date	Mar 1, 2022

Abstract

A system and method for treating a cavity comprises arranging a niobium structure in a coating chamber, the coating chamber being arranged inside a furnace, coating the niobium structure with tin thereby forming an Nb3Sn layer on the niobium structure, and doping the Nb3Sn layer with nitrogen, thereby forming a nitrogen doped Nb3Sn layer on the niobium structure.

First claim

What is claimed is:

1. A method comprising:
arranging a niobium structure in a coating chamber;
coating the niobium structure with tin;
forming an Nb 3 Sn layer on the niobium structure;
doping the Nb 3 Sn layer with nitrogen, wherein doping the Nb 3 Sn layer with nitrogen further comprises:
pressurizing a volume holding the Nb 3 Sn layer with nitrogen gas; and
leaving the Nb 3 Sn layer in the nitrogen gas for at least 1 hour.

2. The method of claim 1 wherein a pressure of the volume holding the Nb 3 Sn layer with the nitrogen gas is at least 1 mTorr and at most 1 Torr.

3. The method of claim 1 further comprising:
cooling the niobium structure after leaving the Nb 3 Sn layer in the nitrogen gas for at least 1 hour.

4. The method of claim 3 further comprising:
venting the volume holding the Nb 3 Sn layer after cooling the niobium structure.

5. The method of claim 1 further comprising:
degassing the coating chamber before coating the niobium structure with tin.

6. The method of claim 5 further comprising:
nucleating the niobium structure after the coating chamber is degassed.

7. The method of claim 1 further comprising:
annealing the niobium structure such that unreacted tin on a surface of the niobium structure evaporates.

8. The method of claim 1 wherein the niobium structure comprises a superconducting radiofrequency cavity.

Assignees

• Fermi Res Alliance Llc

Inventors

• Posen Sam
• Grassellino Anna

Classifications

• C23C14/56

  Apparatus specially adapted for continuous coating; Arrangements for maintaining the vacuum, e.g. vacuum locks · CPC title

• C23C16/54

  Apparatus specially adapted for continuous coating · CPC title

• H01B12/06

  Films or wires on bases or cores · CPC title

• H05H7/20 Primary

  with superconductive walls · CPC title

• C23C16/4485

  by evaporation without using carrier gas in contact with the source material (C23C16/4486 takes precedence) · CPC title