%0 Journal Article
%T Fabrication of Nb/Al2O3/Nb Josephson Junctions using in situ Magnetron Sputtering and Atomic Layer Deposition
%A Rongtao Lu
%A Alan J. Elliot
%A Logan Wille
%A Bo Mao
%A Siyuan Han
%A Judy Z. Wu
%A John Talvacchio
%A Heidi M. Schulze
%A Rupert M. Lewis
%A Daniel J. Ewing
%A H. F. Yu
%A G. M. Xue
%A S. P. Zhao
%J Physics
%D 2013
%I arXiv
%R 10.1109/TASC.2012.2236591
%X Atomic layer deposition (ALD) provides a promising approach for deposition of ultrathin low-defect-density tunnel barriers, and it has been implemented in a high-vacuum magnetron sputtering system for in situ deposition of ALD-Al2O3 tunnel barriers in superconductor-insulator-superconductor (SIS) Josephson junctions. A smooth ALD-Al2O3 barrier layer was grown on a Al-wetted Nb bottom electrode and was followed with a top Nb electrode growth using sputtering. Preliminary low temperature measurements of current-voltage characteristics (IVC) of the Josephson junctions made from these trilayers confirmed the integrity of the ALD-Al2O3 barrier layer. However, the IcRN product of the junctions is much smaller than the value expected from the Ambegaokar-Baratoff formula suggesting a significant pair-breaking mechanism at the interfaces.
%U http://arxiv.org/abs/1309.4410v1