Effect of Chromium Concentration on the Electrical Properties of NiCr Thin Films Resistor Deposited at Room Temperature by Magnetron Cosputtering Technique

NiCr films, 100 nm thick, were prepared on SiO 2 (600 nm)/Si substrates at room temperature as a function of chromium concentration by the cosputtering technique. The crystalline nature and electrical properties of the NiCr films were investigated as a function of chromium concentration. The films with a chromium concentration up to 39% showed a crystalline structure having a low resistivity, a high root-mean-square (rms) roughness, and positive temperature coefficient of resistivity (TCR) values. The films with a chromium concentration above 39% exhibited the amorphous structure with negative TCR values. The TCR values of the films with a chromium concentration of 39 and 42% are approximately +10 and -9 ppm/K, respectively. The TCR values approaching zero can be established by controlling the chromium concentration in the NiCr films.