Superconducting Properties of TiN Films Modulated with Growth Parameters during DC Magnetron Sputtering

Abstract

Transition metal (TM) nitride superconducting films have been continuously studied to apply them for fabricating the superconducting devices operating in the microwave regime. Especially, titanium nitride (TiN) is regarded as a promising candidate to replace pure metal superconductors and be used in quantum processors based on superconducting qubit, microwave kinetic inductance detectors (MKID), superconducting nanowire single photon detectors (SNSPD), and so on, owing to their low loss and high kinetic inductance. In this work, we investigate how the material properties of superconducting TiN films grown by DC magnetron sputtering are influenced by growth conditions such as DC power density and the ratio of N to Ar. The surface morphology and crystallographic structure of each TiN film are characterized by SEM, AFM, and XRD analysis. The highest measured superconducting transition temperature and residual resistivity ratio are found to be ~4.6 K and 1.1867, respectively.