Deposition of Nb3Sn films by multilayer sequential sputtering for SRF cavity application

Conference · Fri Nov 01 00:00:00 EDT 2019

OSTI ID:1647325

Sayeed, Md. N. ^[1]; Elsayed-Ali, H. ^[1]; Burton, M. C. ^[2]; Eremeev, G. V. ^[2]; Reece, C. E. ^[2]; Valente-Feliciano, A-M. ^[2]; Pudasaini, U. ^[3]

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1. Old Dominion Univ., Norfolk, VA (United States)
2. Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States)
3. College of William and Mary, Williamsburg, VA (United States)

Nb3Sn is considered as an alternative of Nb for SRF accelerator cavity application due to its potential to obtain higher quality factors and higher accelerating gradients at a higher operating temperature. Magnetron sputtering is one of the effective techniques that can be used to fabricate Nb3Sn on SRF cavity surface. We report on the surface properties of Nb3Sn films fabricated by sputtering multiple layers of Nb and Sn on sapphire and niobium substrates followed by annealing at 950°C for 3 h. The crystal structure, film microstructure, composition and surface roughness were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), and atomic force microscopy (AFM). The RF performance of the Nb3Sn coated Nb substrates were measured by a surface impedance characterization system. We also report on the design of a multilayer sputter deposition system to coat a single-cell SRF cavity.

• Research Organization: Thomas Jefferson National Accelerator Facility, Newport News, VA (United States)
• Sponsoring Organization: USDOE Office of Science (SC), Nuclear Physics (NP)
• DOE Contract Number: AC05-06OR23177
• OSTI ID: 1647325
• Report Number(s): JLAB-ACC-19-2978; DOE/OR/23177-4723
• Country of Publication: United States
• Language: English