Influence of Al doping and annealing on the microstructures and electrical properties of CrSi films prepared by magnetron co-sputtering

Abstract

In this work, we prepared CrSi films with different Al contents by DC magnetron co-sputtering, and studied the effect of Al content and annealing temperature on the microstructure and electrical properties of the films. The temperature coefficient of resistance (TCR) of the films increases with increasing Al content. Furthermore, the TCR gradually changes from negative to positive value with the increase of the annealing temperature, and reaches zero at a critical temperature. When the Al content is lower than 3.06 at.%, the TCR is always negative after annealing. An excellent combination of high sheet resistance of 5.36 kΩ/sq with near zero TCR of −10.07 ppm/°C were achieved in the films with an Al content of 3.87 at.% after annealing at 520 °C. The stability and crystallinity of the film are improved by the addition of Al element. The mixture of amorphous and crystalline phases results in a near zero TCR. Moreover, the coarsening of the crystalline phase and the increase in spacing of the crystalline phase induces the increase of sheet resistance.