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Niobium-based superconducting nano-devices fabrication using all-metal suspended masks

Sayanti Samaddar, D. M. T. van Zanten, Aurélien Fay, H. Courtois, Clemens B. Winkelmann

Published Aug 18, 2016• 0 citations
OpenAlex

Abstract

Abstract. We report a novel method for the fabrication of superconducting nano-devices based on niobium. The well-known difficulties of lithographic patterning of high-quality niobium are overcome by replacing the usual organic resist mask by a metallic one. The quality of the fabrication procedure is demonstrated by the realization and characterization of long and narrow superconducting lines and niobium-gold-niobium proximity SQUIDs. ar X iv

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Abstract. We report a novel method for the fabrication of superconducting nano-devices based on niobium. The well-known difficulties of lithographic patterning of high-quality niobium are overcome by replacing the usual organic resist mask by a metallic one. The quality of the fabrication procedure is demonstrated by the realization and characterization of long and narrow superconducting lines and niobium-gold-niobium proximity SQUIDs. ar X iv
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We have developed a fabrication technique for Josephson junctions that employs a three-dimensional patterned, low-loss substrate instead of commonly used organic resists. The technique enables the fabrication of high-quality trilayer junctions from a wide range of geometries and materials, including high-melting-point superconductors such as tantalum or niobium. The junction electrodes are free from intentionally introduced oxides and organic materials, which are known sources of decoherence. We fabricate and characterize underdamped Nb/AlOx/Nb junctions of different sizes in several geometries.
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