Influence ScN protective thin layer on the superconducting properties of ultrathin NbN films

TL;DR

This study investigates how a thin scandium nitride (ScN) protective layer influences the superconducting and microstructural properties of ultrathin niobium nitride (NbN) films, especially under high-temperature annealing in oxygen-rich environments.

Contribution

It is the first to examine the effects of ScN coating on NbN films' superconducting properties and their resistance to high-temperature annealing and corrosion.

Findings

ScN layer acts as an effective protective barrier during annealing.

Adding ScN increases NbN film resistance to corrosion.

ScN coating does not significantly alter NbN film density or thickness.

Abstract

The present study delves into exploring the impact of a thin protective layer of scandium nitride (ScN) on the superconductive properties of thin films of niobium nitride (NbN) generated through reactive magnetron deposition. This is the first time such an investigation has been carried out. The article offers a comprehensive investigation of the morphological, microstructural, and electrophysical features of thin films that have undergone high-temperature annealing in an oxygen-rich environment. The dependence of the critical transition temperature of the NbN thin film on the annealing temperature of the samples in an oxygen medium, with and without ScN coating, was determined. According to X-ray reflectometry studies, it has been observed that the ScN film serves as a protective layer, even when exposed to annealing temperatures of approximately 450{\deg}C, without significantly affecting the NbN layer density or thickness. It has been shown that adding a ScN coating to a thin NbN film increases its resistance to corrosive media compared to a film without the coating.