Flexible NbTiN thin films for superconducting electronics

We compare the superconducting properties of 100 nm thick NbTiN films grown by reactive sputtering on silicon and flexible commercial polyimide. The samples are fabricated by co-sputtering using Nb and Ti targets at room temperature with a reactive atmosphere of N2 and Ar. The films display a polycrystalline structure and superconducting critical temperatures of 13.2 K on polyimide and 13.4 K on silicon. The analysis of the upper critical field reveals huge values, with extrapolation to zero close to 29 T for films on silicon and 23 T for those on polyimide. A comparison of the superconducting transition applying mechanical deformation is shown. Presenting a higher superconducting gap and upper critical fields above than the commonly used elemental Nb, the development of NbTiN thin films on flexible polyimide appears as a potential material for application in superconducting electronics.

Automated summary

We compared the superconducting properties of 100 nm thick NbTiN films grown on silicon and flexible polyimide. The superconducting critical temperatures were 13.2 K on polyimide and 13.4 K on silicon, while the upper critical field values were around 29 T on silicon and 23 T on polyimide. The comparison of superconducting transition under mechanical deformation showed that NbTiN thin films on flexible polyimide have a higher superconducting gap and upper critical fields, making them potential materials for superconducting electronics.