Structural and electrical properties of NiCr thin films annealed at various temperatures in a vacuum and a nitrogen ambient for π-type attenuator applications

NiCr thin films were prepared on SiO2/Si substrates using a magnetron co-sputtering technique and were annealed at various temperatures in a vacuum (3 X 10(- 6) Torr) and a nitrogen ambient. The crystallinity of the films annealed in a vacuum ambient was higher than that of films annealed in nitrogen ambient. Samples annealed above 500 degrees C in nitrogen ambient exhibited a second phase in the NiCr films. The incorporation of oxygen into the NiCr films produced the decrease of crystallinity and significantly influenced the temperature coefficient of resistance of the films. (c) 2006 The Electrochemical Society.