IPAC2012 - List of Authors (Gu, D.)

Paper	Title	Page
WEPPC096	Exploring the Effect of AL2O3 ALD Coating on a High Gradient ILC Single-Cell Cavity	2441
	G.V. Eremeev, A-M. Valente-Feliciano, A.T. Wu JLAB, Newport News, Virginia, USA D. Gu ODU, Norfolk, Virginia, USA
	Funding: Authored by Jefferson Science Associates, LLC under U.S. DOE Contract No. DE-AC05-06OR23177. Encouraged by work at Argonne National Lab, we investigated atomic layer deposition technique for high gradient superconducting RF cavities at JLab with an ALD coating system of Old Dominion University located on the JLab site. The goal of this study was to look into the possibility of coating a dielectric layer on top of RF niobium surface at a lower temperature of 120 C as compared to ANL coatings at 200 C in order to preserve niobium pentooxide on niobium surface. The initial coatings showed complete, but non-uniform coatings of the surface with several areas exhibiting discoloration, which was probably due to the temperature variation during coatings. The initial coating showed a high RF losses, which were improved after discolored areas on the beam tubes were removed with HF rinse of the beam tubes only. The best result was 2·10⁹ low field Q0 and Eacc = 18 MV/m limited by available power.

Paper

Title

Page

Exploring the Effect of AL2O3 ALD Coating on a High Gradient ILC Single-Cell Cavity

2441

G.V. Eremeev, A-M. Valente-Feliciano, A.T. Wu
JLAB, Newport News, Virginia, USA
D. Gu
ODU, Norfolk, Virginia, USA

Funding: Authored by Jefferson Science Associates, LLC under U.S. DOE Contract No. DE-AC05-06OR23177.
Encouraged by work at Argonne National Lab, we investigated atomic layer deposition technique for high gradient superconducting RF cavities at JLab with an ALD coating system of Old Dominion University located on the JLab site. The goal of this study was to look into the possibility of coating a dielectric layer on top of RF niobium surface at a lower temperature of 120 C as compared to ANL coatings at 200 C in order to preserve niobium pentooxide on niobium surface. The initial coatings showed complete, but non-uniform coatings of the surface with several areas exhibiting discoloration, which was probably due to the temperature variation during coatings. The initial coating showed a high RF losses, which were improved after discolored areas on the beam tubes were removed with HF rinse of the beam tubes only. The best result was 2·10⁹ low field Q0 and Eacc = 18 MV/m limited by available power.