Optimization of the deposition and annealing of CuAIMo thin film resistors

This paper studies the effect of varying deposition and annealing process parameters on the electrical performance and structural properties of a novel CuAlMo thin film resistor material. The design of experiments (DOE) and analysis of variance (ANOVA) methods were utilized to determine the optimum process conditions for the films which were prepared using DC magnetron sputtering before being annealed in air ambient. Films of low sheet resistance with near zero temperature coefficient of resistance (TCR) and good long term stability were obtained at a high deposition rate and low sputtering pressure. Subsequent annealing of the films in air resulted in further crystallization with grain growth and stress relief which gave an increase in conductivity and TCR. In addition to the deposition parameters, the stability of the film was also shown to improve with increasing heat treatment time and temperature.