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Sputter deposition conditions and penetration depth in NbN thin films

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Abstract

NbN films have been reactively sputter deposited from a 15.24 cm Nb target using a variety of deposition conditions. Film penetration depth has been measured using Taber's parallel plate resonator technique. These measurements have been compared with penetration depth measurements obtained from SQUID measurements. Penetration depth results have also been correlated with film superconducting transition temperature, resistivity, resistance ratio, and x-ray diffraction patterns. The films have been deposited over a variety of substrates and buffer layers including oxidized Si, sapphire, and a variety of metal and metal nitride "seed" layers.

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... The penetration depth of the films has been inferred using the parallel plate resonator technique, as described in the article by Taber [12]. This method has been previously used to determine the penetration depth of NbN films [13]. The measurement procedure is as follows. ...
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