Effect of annealing on the superconducting properties of a-Nb(x)Si(1-x) thin films

Abstract

a-Nb(x)Si(1-x) thin films with thicknesses down to 25 Å have been structurally characterized by TEM (Transmission Electron Microscopy) measurements. As-deposited or annealed films are shown to be continuous and homogeneous in composition and thickness, up to an annealing temperature of 500°C. We have carried out low temperature transport measurements on these films close to the superconductor-to-insulator transition (SIT), and shown a qualitative difference between the effect of annealing or composition, and a reduction of the film thickness on the superconducting properties of a-NbSi. These results question the pertinence of the sheet resistance R_square as the relevant parameter to describe the SIT.

arXiv comment9 pages, 12 figures

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Cited by in corpus (9)

• Spectroscopic evidence for strong correlations between local superconducting gap and local Altshuler-Aronov density-of-states suppression in ultrathin NbN films
• Emergence of Quantum Phase-Slip Behaviour in Superconducting NbN Nanowires: DC Electrical Transport and Fabrication Technologies
• Dissipative phases across the superconductor-to-insulator transition
• Overactivated transport in the localized phase of the superconductor-insulator transition
• Destruction of superconductivity in disordered materials : a dimensional crossover
• Observation of thermally activated glassiness and memory dip in a-NbSi insulating thin films
• Electron glass effects in amorphous NbSi films
• Electron glass signatures up to room temperature in disordered insulators
• Sample-based calibration for cryogenic broadband microwave reflectometry measurements