SRF2021 - List of Keywords (target)

Paper	Title	Other Keywords	Page
SUPCAV008	Design and Construction of Nb₃Sn Vapor Diffusion Coating System at KEK	cavity, vacuum, radio-frequency, MMI	23
	K. Takahashi, T. Okada Sokendai, Ibaraki, Japan H. Ito, E. Kako, T. Konomi, H. Sakai, K. Umemori KEK, Ibaraki, Japan
	Vapor diffusion Nb₃Sn coating system was developed at KEK. At most 1.3GHz 3-cell cavity can be coat with the coating system. The coating system consists of a coating chamber made of Nb, a vacuum furnace for heating the Nb chamber, and a heating device of Tin in the crucible. The Nb chamber vacuum and the furnace vacuum are isolated to prevent contamination from the furnace. There is a heating device for increasing Tin vapor pressure. In this presentation, the design and construction of the coating system are reported.
	Poster SUPCAV008 [0.986 MB]
DOI •	reference for this paper ※ doi:10.18429/JACoW-SRF2021-SUPCAV008
About •	Received ※ 21 June 2021 — Accepted ※ 18 November 2021 — Issue date ※ 11 April 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

SUPFDV009	Thermal Annealing of Sputtered Nb₃Sn and V₃Si Thin Films for Superconducting RF Cavities	SRF, cavity, ECR, radio-frequency	82
	K. Howard, M. Liepe, Z. Sun Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA
	Funding: U.S. National Science Foundation under Award PHY-1549132, the Center for Bright Beams and Cornell Center for Materials Research Shared Facilities supported through the NSF MRSEC program (DMR-1719875) Nb₃Sn and V₃Si thin films are alternative material candidates for the next-generation of superconducting radio frequency (SRF) cavities. However, past sputtered films suffer from stoichiometry and strain issues during deposition and post annealing. As such, we aim to explore the structural and chemical effects of thermal annealing, both in-situ and post-sputtering, on DC-sputtered Nb₃Sn and V₃Si with varying thickness on Nb or Cu substrates. We successfully enabled recrystallization of 100 nm thin Nb₃Sn films with stoichiometric and strain-free grains at 950 C annealing. For 2 um films, we observed removal of strain and slight increase in grain size with increasing temperature. A phase transformation from unstable to stable structure appeared on thick V₃Si samples, while we observed significant Sn loss in thick Nb₃Sn films at high temperature anneals. For films on Cu substrates, we observed similar Sn and Si loss during annealing likely due to Cu-Sn and Cu-Si phase generation and subsequent Sn and Si evaporation. These results encourage us to refine our process to obtain high quality films for SRF use.
DOI •	reference for this paper ※ doi:10.18429/JACoW-SRF2021-SUPFDV009
About •	Received ※ 22 June 2021 — Revised ※ 06 July 2021 — Accepted ※ 12 August 2021 — Issue date ※ 17 March 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPTEV012	Extra-Cold EP Process at Fermilab	cavity, controls, niobium, SRF	230
	F. Furuta, D.J. Bice, M. Martinello, T.J. Ring Fermilab, Batavia, Illinois, USA
	FNAL has established a cold Electro-Polishing (EP) method which maintains the outer surface temperature of cavity cell around 12~15°C during EP process. Cold EP has been applied on the various SRF cavities and contributed to achieve high RF performances with them. To investigate more feasibility and capability of EP at lower temperature, the FNAL EP temperature control tool was recently improved. Extra-cold EP process below 0°C at cavity cell region was successfully performed on 1.3 GHz 1-cell cavity. A compatible RF performance with cold EP method was also demonstrated during the cavity vertical testing. The details of extra-cold EP process and the cavity test results will be presented.
	Poster MOPTEV012 [2.038 MB]
DOI •	reference for this paper ※ doi:10.18429/JACoW-SRF2021-MOPTEV012
About •	Received ※ 21 June 2021 — Accepted ※ 14 December 2021 — Issue date ※ 16 May 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPCAV006	Nb₃Sn Films Depositions from Targets Synthesized via Liquid Tin Diffusion	niobium, cavity, controls, site	452
	M. Zanierato, O. Azzolini, E. Chyhyrynets, V.A. Garcia Diaz, G. Keppel, C. Pira, F. Stivanello INFN/LNL, Legnaro (PD), Italy
	The deposition of Nb₃Sn on copper cavities is inter-esting for the higher thermal conductivity of copper compared to common Nb substrates. The better heat exchange would allow the use of cryocoolers reducing cryogenic costs and the risk of thermal quench [1]. Magnetron sputtering technology allows the deposi-tion of Nb₃Sn on substrates different than Nb, however the coating of substrates with complex geometry (such as elliptical cavities) may require targets with non-planar shape, difficult to realize with classic powder sintering techniques. In this work, the possibility of using the Liquid Tin Diffusion (LTD) technique to produce sputtering targets is explored. The LTD tech-nique is a wire fabrication technology, already devel-oped in the past at LNL for SRF applications [2], that allows the deposition of very thick and uniform coat-ing on Nb substrates even with complex geometry [3]. Improvements in LTD process, proof of concept of a single use LTD target production, and characterization of the Nb₃Sn film coated by DC magnetron sputtering with these innovative targets are reported in this work.
	Poster TUPCAV006 [5.037 MB]
DOI •	reference for this paper ※ doi:10.18429/JACoW-SRF2021-TUPCAV006
About •	Received ※ 21 June 2021 — Revised ※ 12 July 2021 — Accepted ※ 23 August 2021 — Issue date ※ 02 September 2021
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEOCAV03	RF Dipole Crab Cavity Testing for HL-LHC	cavity, HOM, dipole, controls	687
	N. Valverde Alonso, R. Calaga, S.J. Calvo, O. Capatina, O. Capatina, A. Castilla, M. Chiodini, C. Duval, L.M.A. Ferreira, M. Gourragne, P.J. Kohler, T. Mikkola, J.A. Mitchell, E. Montesinos, C. Pasquino, G. Pechaud, N. Stapley, M. Therasse, K. Turaj, J.D. Walker CERN, Meyrin, Switzerland A. Castilla Cockcroft Institute, Lancaster University, Lancaster, United Kingdom A. Castilla Lancaster University, Lancaster, United Kingdom
	RF Crab Cavities are an essential element of the High Luminosity LHC (HL-LHC) upgrade at CERN. Two RF dipole crab cavity used for the compensation of the horizontal crossing angle were recently manufactured and integrated into Titanium Helium tank and RF ancillaries necessary for the beam operation. The two cavities will be integrated into a cryomodule in collaboration with UK-STFC and tested with proton beams in the SPS in 2023. This paper will highlight the RF measurements during the important manufacturing steps, surface preparation and cavity performance at 2K.
DOI •	reference for this paper ※ doi:10.18429/JACoW-SRF2021-WEOCAV03
About •	Received ※ 18 June 2021 — Revised ※ 07 September 2021 — Accepted ※ 16 September 2021 — Issue date ※ 22 November 2021
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPCAV014	Development of High-Q Treatments for PIP-II Prototype Cavities at LASA-INFN	cavity, SRF, niobium, electron	820
	M. Bertucci, A. Bosotti, A. D’Ambros, A.T. Grimaldi, P. Michelato, L. Monaco, C. Pagani, R. Paparella, D. Sertore INFN/LASA, Segrate (MI), Italy A. Gresele, A. Torri Ettore Zanon S.p.A., Nuclear Division, Schio, Italy C. Pagani Università degli Studi di Milano & INFN, Segrate, Italy M. Rizzi Ettore Zanon S.p.A., Schio, Italy
	INFN-LASA is currently involved in the production of PIP-II low-beta cavity prototypes. The main challenge of this activity is to develop a state-of-the art surface treatment recipe on such cavity geometry, to achieve the high-Q target required for cavity operation in the linac. This paper reports the status of cavity treatments development and the first cold test results of a single-cell cavity. This cavity has undergone a baseline treatment based on Electropolishing as bulk removal step. Being this test successful, a strategy for pushing the cavities towards higher performances is here proposed.
DOI •	reference for this paper ※ doi:10.18429/JACoW-SRF2021-THPCAV014
About •	Received ※ 21 June 2021 — Accepted ※ 01 March 2022 — Issue date ※ 01 May 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPTEV015	Cylindrical Magnetron Development for Nb3sn Deposition via Magnetron Sputtering	cavity, SRF, site, radio-frequency	868
	Md.N. Sayeed, H. Elsayed-Ali ODU, Norfolk, Virginia, USA C. Côté, M.A. Farzad, A. Sarkissian PLASMIONIQUE Inc., Varennes, Québec, Canada G.V. Eremeev Fermilab, Batavia, Illinois, USA A-M. Valente-Feliciano JLab, Newport News, Virginia, USA
	Funding: This work was supported by the U.S. Department of Energy, Office of Science, Office of Nuclear Physics under Contract No. DE-AC05-06OR23177. Due to its better superconducting properties (critical temperature Tc~ 18.3 K, superheating field Hsh~ 400 mT), Nb₃Sn is considered as a potential alternative to niobium (Tc~ 9.25 K, Hsh~ 200 mT) for superconducting radiofrequency (SRF) cavities for particle acceleration. Magnetron sputtering is an effective method to produce superconducting Nb₃Sn films. We deposited superconducting Nb₃Sn films on samples with magnetron sputtering using co-sputtering, sequential sputtering, and sputtering from a stoichiometric target. Nb₃Sn films produced by magnetron sputtering in our previous experiments have achieved DC superconducting critical temperature up to 17.93 K and RF superconducting transition at 17.2 K. A magnetron sputtering system with two identical cylindrical cathodes that can be used to sputter Nb₃Sn films on cavities has been designed and is under development now. We report on the design and the current progress on the development of the system.
	Poster THPTEV015 [1.131 MB]
DOI •	reference for this paper ※ doi:10.18429/JACoW-SRF2021-THPTEV015
About •	Received ※ 22 June 2021 — Revised ※ 12 August 2021 — Accepted ※ 21 August 2021 — Issue date ※ 27 September 2021
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

FROFDV06	Synthesis of Nb and Alternative Superconducting Film to Nb for SRF Cavity as Single Layer	site, cavity, SRF, niobium	893
	R. Valizadeh, P. Goudket, A.N. Hannah, O.B. Malyshev STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom C.Z. Antoine CEA-DRF-IRFU, France C.Z. Antoine CEA-IRFU, Gif-sur-Yvette, France E. Chyhyrynets, C. Pira INFN/LNL, Legnaro (PD), Italy P. Goudket, O.B. Malyshev, D.J. Seal, B.S. Sian, D.A. Turner Cockcroft Institute, Warrington, Cheshire, United Kingdom O. Kugeler, D.B. Tikhonov HZB, Berlin, Germany S.B. Leith, A.O. Sezgin, M. Vogel University Siegen, Siegen, Germany A. Medvids, P. Onufrijevs Riga Technical University, Riga, Latvia D.J. Seal, B.S. Sian, D.A. Turner Lancaster University, Lancaster, United Kingdom G.B.G. Stenning STFC/RAL/ISIS, Chilton, Didcot, Oxon, United Kingdom A. Sublet, G. Vandoni, L. Vega Cid, W. Venturini Delsolaro, P. Vidal García CERN, Meyrin, Switzerland
	"Bulk niobium (Nb) has been the material of choice for superconducting RF (SRF) cavities but for further improvement in cavity RF performance, one may have to turn to films of Nb and to other superconducting materials deposited on copper as thermal and mechanical support. Other materials known as A15, such as Nb₃Sn or V₃Si and B1 such as NbTiN and NbN are much easier to synthesise in thin films rather than being made as bulk cavity. The potential benefits of using materials other than Nb would be a higher Tc, a potentially higher critical held Hc, leading to potentially significant cryogenics cost reduction if the cavity operation temperature is 4.2 K or higher. We report on optimising deposition parameters and effect of substrate treatment prior to deposition for successful synthesising of Nb and the alternative superconducting thin film with high superconducting properties (Tc and Hsh) on flat substrates and QPR samples in single layer. The DC and RF SC properties have been tested using PPMS and QPR measurements. This work is part of the H2020 ARIES collaboration. We further report on preparation of RF cavities employing these alternative material for future cavity production."
DOI •	reference for this paper ※ doi:10.18429/JACoW-SRF2021-FROFDV06
About •	Received ※ 21 June 2021 — Accepted ※ 05 January 2022 — Issue date ※ 28 April 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

Paper

Title

Other Keywords

Page

SUPCAV008

Design and Construction of Nb₃Sn Vapor Diffusion Coating System at KEK

cavity, vacuum, radio-frequency, MMI

23

K. Takahashi, T. Okada
Sokendai, Ibaraki, Japan
H. Ito, E. Kako, T. Konomi, H. Sakai, K. Umemori
KEK, Ibaraki, Japan

Vapor diffusion Nb₃Sn coating system was developed at KEK. At most 1.3GHz 3-cell cavity can be coat with the coating system. The coating system consists of a coating chamber made of Nb, a vacuum furnace for heating the Nb chamber, and a heating device of Tin in the crucible. The Nb chamber vacuum and the furnace vacuum are isolated to prevent contamination from the furnace. There is a heating device for increasing Tin vapor pressure. In this presentation, the design and construction of the coating system are reported.

Poster SUPCAV008 [0.986 MB]

DOI •

reference for this paper ※ doi:10.18429/JACoW-SRF2021-SUPCAV008

About •

Received ※ 21 June 2021 — Accepted ※ 18 November 2021 — Issue date ※ 11 April 2022

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

SUPFDV009

Thermal Annealing of Sputtered Nb₃Sn and V₃Si Thin Films for Superconducting RF Cavities

SRF, cavity, ECR, radio-frequency

82

K. Howard, M. Liepe, Z. Sun
Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA

Funding: U.S. National Science Foundation under Award PHY-1549132, the Center for Bright Beams and Cornell Center for Materials Research Shared Facilities supported through the NSF MRSEC program (DMR-1719875)
Nb₃Sn and V₃Si thin films are alternative material candidates for the next-generation of superconducting radio frequency (SRF) cavities. However, past sputtered films suffer from stoichiometry and strain issues during deposition and post annealing. As such, we aim to explore the structural and chemical effects of thermal annealing, both in-situ and post-sputtering, on DC-sputtered Nb₃Sn and V₃Si with varying thickness on Nb or Cu substrates. We successfully enabled recrystallization of 100 nm thin Nb₃Sn films with stoichiometric and strain-free grains at 950 C annealing. For 2 um films, we observed removal of strain and slight increase in grain size with increasing temperature. A phase transformation from unstable to stable structure appeared on thick V₃Si samples, while we observed significant Sn loss in thick Nb₃Sn films at high temperature anneals. For films on Cu substrates, we observed similar Sn and Si loss during annealing likely due to Cu-Sn and Cu-Si phase generation and subsequent Sn and Si evaporation. These results encourage us to refine our process to obtain high quality films for SRF use.

DOI •

reference for this paper ※ doi:10.18429/JACoW-SRF2021-SUPFDV009

About •

Received ※ 22 June 2021 — Revised ※ 06 July 2021 — Accepted ※ 12 August 2021 — Issue date ※ 17 March 2022

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPTEV012

Extra-Cold EP Process at Fermilab

cavity, controls, niobium, SRF

230

F. Furuta, D.J. Bice, M. Martinello, T.J. Ring
Fermilab, Batavia, Illinois, USA

FNAL has established a cold Electro-Polishing (EP) method which maintains the outer surface temperature of cavity cell around 12~15°C during EP process. Cold EP has been applied on the various SRF cavities and contributed to achieve high RF performances with them. To investigate more feasibility and capability of EP at lower temperature, the FNAL EP temperature control tool was recently improved. Extra-cold EP process below 0°C at cavity cell region was successfully performed on 1.3 GHz 1-cell cavity. A compatible RF performance with cold EP method was also demonstrated during the cavity vertical testing. The details of extra-cold EP process and the cavity test results will be presented.

Poster MOPTEV012 [2.038 MB]

DOI •

reference for this paper ※ doi:10.18429/JACoW-SRF2021-MOPTEV012

About •

Received ※ 21 June 2021 — Accepted ※ 14 December 2021 — Issue date ※ 16 May 2022

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPCAV006

Nb₃Sn Films Depositions from Targets Synthesized via Liquid Tin Diffusion

niobium, cavity, controls, site

452

M. Zanierato, O. Azzolini, E. Chyhyrynets, V.A. Garcia Diaz, G. Keppel, C. Pira, F. Stivanello
INFN/LNL, Legnaro (PD), Italy

The deposition of Nb₃Sn on copper cavities is inter-esting for the higher thermal conductivity of copper compared to common Nb substrates. The better heat exchange would allow the use of cryocoolers reducing cryogenic costs and the risk of thermal quench [1]. Magnetron sputtering technology allows the deposi-tion of Nb₃Sn on substrates different than Nb, however the coating of substrates with complex geometry (such as elliptical cavities) may require targets with non-planar shape, difficult to realize with classic powder sintering techniques. In this work, the possibility of using the Liquid Tin Diffusion (LTD) technique to produce sputtering targets is explored. The LTD tech-nique is a wire fabrication technology, already devel-oped in the past at LNL for SRF applications [2], that allows the deposition of very thick and uniform coat-ing on Nb substrates even with complex geometry [3]. Improvements in LTD process, proof of concept of a single use LTD target production, and characterization of the Nb₃Sn film coated by DC magnetron sputtering with these innovative targets are reported in this work.

Poster TUPCAV006 [5.037 MB]

DOI •

reference for this paper ※ doi:10.18429/JACoW-SRF2021-TUPCAV006

About •

Received ※ 21 June 2021 — Revised ※ 12 July 2021 — Accepted ※ 23 August 2021 — Issue date ※ 02 September 2021

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEOCAV03

RF Dipole Crab Cavity Testing for HL-LHC

cavity, HOM, dipole, controls

687

N. Valverde Alonso, R. Calaga, S.J. Calvo, O. Capatina, O. Capatina, A. Castilla, M. Chiodini, C. Duval, L.M.A. Ferreira, M. Gourragne, P.J. Kohler, T. Mikkola, J.A. Mitchell, E. Montesinos, C. Pasquino, G. Pechaud, N. Stapley, M. Therasse, K. Turaj, J.D. Walker
CERN, Meyrin, Switzerland
A. Castilla
Cockcroft Institute, Lancaster University, Lancaster, United Kingdom
A. Castilla
Lancaster University, Lancaster, United Kingdom

RF Crab Cavities are an essential element of the High Luminosity LHC (HL-LHC) upgrade at CERN. Two RF dipole crab cavity used for the compensation of the horizontal crossing angle were recently manufactured and integrated into Titanium Helium tank and RF ancillaries necessary for the beam operation. The two cavities will be integrated into a cryomodule in collaboration with UK-STFC and tested with proton beams in the SPS in 2023. This paper will highlight the RF measurements during the important manufacturing steps, surface preparation and cavity performance at 2K.

DOI •

reference for this paper ※ doi:10.18429/JACoW-SRF2021-WEOCAV03

About •

Received ※ 18 June 2021 — Revised ※ 07 September 2021 — Accepted ※ 16 September 2021 — Issue date ※ 22 November 2021

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPCAV014

Development of High-Q Treatments for PIP-II Prototype Cavities at LASA-INFN

cavity, SRF, niobium, electron

820

M. Bertucci, A. Bosotti, A. D’Ambros, A.T. Grimaldi, P. Michelato, L. Monaco, C. Pagani, R. Paparella, D. Sertore
INFN/LASA, Segrate (MI), Italy
A. Gresele, A. Torri
Ettore Zanon S.p.A., Nuclear Division, Schio, Italy
C. Pagani
Università degli Studi di Milano & INFN, Segrate, Italy
M. Rizzi
Ettore Zanon S.p.A., Schio, Italy

INFN-LASA is currently involved in the production of PIP-II low-beta cavity prototypes. The main challenge of this activity is to develop a state-of-the art surface treatment recipe on such cavity geometry, to achieve the high-Q target required for cavity operation in the linac. This paper reports the status of cavity treatments development and the first cold test results of a single-cell cavity. This cavity has undergone a baseline treatment based on Electropolishing as bulk removal step. Being this test successful, a strategy for pushing the cavities towards higher performances is here proposed.

DOI •

reference for this paper ※ doi:10.18429/JACoW-SRF2021-THPCAV014

About •

Received ※ 21 June 2021 — Accepted ※ 01 March 2022 — Issue date ※ 01 May 2022

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPTEV015

Cylindrical Magnetron Development for Nb3sn Deposition via Magnetron Sputtering

cavity, SRF, site, radio-frequency

868

Md.N. Sayeed, H. Elsayed-Ali
ODU, Norfolk, Virginia, USA
C. Côté, M.A. Farzad, A. Sarkissian
PLASMIONIQUE Inc., Varennes, Québec, Canada
G.V. Eremeev
Fermilab, Batavia, Illinois, USA
A-M. Valente-Feliciano
JLab, Newport News, Virginia, USA

Funding: This work was supported by the U.S. Department of Energy, Office of Science, Office of Nuclear Physics under Contract No. DE-AC05-06OR23177.
Due to its better superconducting properties (critical temperature Tc~ 18.3 K, superheating field Hsh~ 400 mT), Nb₃Sn is considered as a potential alternative to niobium (Tc~ 9.25 K, Hsh~ 200 mT) for superconducting radiofrequency (SRF) cavities for particle acceleration. Magnetron sputtering is an effective method to produce superconducting Nb₃Sn films. We deposited superconducting Nb₃Sn films on samples with magnetron sputtering using co-sputtering, sequential sputtering, and sputtering from a stoichiometric target. Nb₃Sn films produced by magnetron sputtering in our previous experiments have achieved DC superconducting critical temperature up to 17.93 K and RF superconducting transition at 17.2 K. A magnetron sputtering system with two identical cylindrical cathodes that can be used to sputter Nb₃Sn films on cavities has been designed and is under development now. We report on the design and the current progress on the development of the system.

Poster THPTEV015 [1.131 MB]

DOI •

reference for this paper ※ doi:10.18429/JACoW-SRF2021-THPTEV015

About •

Received ※ 22 June 2021 — Revised ※ 12 August 2021 — Accepted ※ 21 August 2021 — Issue date ※ 27 September 2021

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

FROFDV06

Synthesis of Nb and Alternative Superconducting Film to Nb for SRF Cavity as Single Layer

site, cavity, SRF, niobium

893

R. Valizadeh, P. Goudket, A.N. Hannah, O.B. Malyshev
STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom
C.Z. Antoine
CEA-DRF-IRFU, France
C.Z. Antoine
CEA-IRFU, Gif-sur-Yvette, France
E. Chyhyrynets, C. Pira
INFN/LNL, Legnaro (PD), Italy
P. Goudket, O.B. Malyshev, D.J. Seal, B.S. Sian, D.A. Turner
Cockcroft Institute, Warrington, Cheshire, United Kingdom
O. Kugeler, D.B. Tikhonov
HZB, Berlin, Germany
S.B. Leith, A.O. Sezgin, M. Vogel
University Siegen, Siegen, Germany
A. Medvids, P. Onufrijevs
Riga Technical University, Riga, Latvia
D.J. Seal, B.S. Sian, D.A. Turner
Lancaster University, Lancaster, United Kingdom
G.B.G. Stenning
STFC/RAL/ISIS, Chilton, Didcot, Oxon, United Kingdom
A. Sublet, G. Vandoni, L. Vega Cid, W. Venturini Delsolaro, P. Vidal García
CERN, Meyrin, Switzerland

"Bulk niobium (Nb) has been the material of choice for superconducting RF (SRF) cavities but for further improvement in cavity RF performance, one may have to turn to films of Nb and to other superconducting materials deposited on copper as thermal and mechanical support. Other materials known as A15, such as Nb₃Sn or V₃Si and B1 such as NbTiN and NbN are much easier to synthesise in thin films rather than being made as bulk cavity. The potential benefits of using materials other than Nb would be a higher Tc, a potentially higher critical held Hc, leading to potentially significant cryogenics cost reduction if the cavity operation temperature is 4.2 K or higher. We report on optimising deposition parameters and effect of substrate treatment prior to deposition for successful synthesising of Nb and the alternative superconducting thin film with high superconducting properties (Tc and Hsh) on flat substrates and QPR samples in single layer. The DC and RF SC properties have been tested using PPMS and QPR measurements. This work is part of the H2020 ARIES collaboration. We further report on preparation of RF cavities employing these alternative material for future cavity production."

DOI •

reference for this paper ※ doi:10.18429/JACoW-SRF2021-FROFDV06

About •

Received ※ 21 June 2021 — Accepted ※ 05 January 2022 — Issue date ※ 28 April 2022

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)