Optimization of Co-sputtering Process for High-performance Piezoelectric Films

This study investigated the deposition rates and elemental concentrations of aluminum (Al) and scandium (Sc) under different sputtering conditions. Using Pulse DC and RF sputtering techniques, we explored the linear relationships between deposition rate and power for both elements. The results showed that, across different power settings, the deposition rate of Al was consistently higher than that of Sc, with a ratio of approximately 1.1. Under co-sputtering conditions, we analyzed the relationship between power ratio and element concentration ratio, finding that this relationship was closer to linear under Pulse DC conditions, but less so under RF conditions. Additionally, we observed that the deposition rates of Al and Sc during co-sputtering were lower than those during single sputtering, likely due to the formation of a more densely packed crystal structure. Finally, we assessed the effect of nitrogen flow rate on the nitrogen content in the films, showing that the ratio of nitrogen atoms to the total number of Al and Sc atoms remained stable under the same flow conditions. These findings provide valuable insights for optimizing film preparation processes and developing films with specific composition ratios.