Post annealing effects on low temperature deposited Mn-Co-Ni-O films by radio frequency magnetron sputtering

Mn1.56Co0.96Ni0.48O4 (MCN) thin films were deposited on amorphous Al2O3 substrates by radio frequency magnetron sputtering at a relatively low temperature (450 °C). The films were annealed at 450 °C, 600 °C and 750 °C for 20 min respectively. The structural property was characterized and the result indicated post annealing had important impact on crystallinity and surface morphology of the films. Temperature dependent resistivity test revealed that the MCN films possess moderate resistivity, low negative temperature coefficient and favorable characteristic temperature. The method of preparing MCN films with favorable performance at 450 °C is expected to be compatible with standard silicon industry process and has great significance for developing linear or focal plane devices with MCN thin film.