Emergence of near-zero temperature coefficient of resistance in the Mn3CuN antiperovskite thin film structure

• Growth of Mn 3 CuN thin films with near-zero temperature coefficient of resistance (TCR). • Decreasing deposition pressure improves film density and resistance stability. • Heat treatment forms protective MnO layer to fine tune electrical properties. • Mn 3 CuN films grown at 0.2 Pa have TCR < 6 ppm/°C and resistance stability < 0.6 %. Thin film material systems with extremely low temperature coefficient of resistance (TCR) are highly sought for the fabrication of high precision electronic devices to replace existing nichrome and tantalum nitride technologies. Using reactive magnetron sputtering in a mixed argon/nitrogen atmosphere we produced Mn 3 CuN antiperovskite thin film structures and by careful control of the deposition parameters, reveal the emergence of near-zero TCR values. Optimum properties were obtained for films deposited at 0.2–0.3 Pa in a 17 % partial nitrogen plasma environment and following heat treatment (nitrogen at 325 °C) and stabilisation (air at 260 °C), with average TCR values reaching −6 ppm/°C and resistance stability as low as 0.57 % for unprotected films. We present full compositional, morphological and structural characterisation of the films and demonstrate that dense and stable Mn 3 CuN antiperovskite structures can be successfully grown by reactive magnetron sputtering for the future development of high precision thin film resistive components.