Statistical approach for the optimal deposition of SmCo layer for SmCo/Cr magnetic films

Abstract

The quality of sputtered-deposited SmCo/Cr films used for high-density magnetic recording media depends on several sputtering factors of the SmCo magnetic layer. The investigation into the optimal sputtering conditions needs a large number of experiments. The orthogonal design of experiments and the analysis of variance are considered effective methods, which not only minimize the number of experiments but also optimize the sputtering condition of the SmCo layer for high coercivity of SmCo/Cr films. Using the orthogonal design of experiments, the effects of four factors, such as target–substrate distance, DC power, sputtering pressure and sputtering time, were simultaneously investigated by only nine experiments. It is found that target–substrate distance, DC power and the sputtering pressure are very important factors for coercivity, while the effect of sputtering time is not obvious. In addition, the optimal condition of the SmCo layer was obtained. It can be proved that the results of our experiment are at the 95% level.