Structural and Hardness Characteristics of Silicon Nitride Thin Films Deposited on Metallic Substrates by DC Reactive Sputtering Technique

In this work, silicon nitride thin films were prepared by dc reactive magnetron sputtering technique using silicon targets with different type of conductivity (n-type and p-type) as well as different gas mixture (50:50 and 70:30). The structural and hardness characteristics of the prepared films were determined as functions of type of conductivity and gas mixing ratio. The obtained results showed that using gas mixture with lower content of nitrogen lead to prepare silicon nitride nanostructures with residual unbounded silicon atoms. Also, larger particles were produced when using gas mixture with lower nitrogen content. As well, preparation of silicon nitride nanostructures from n-type silicon target resulted in higher homogeneity than those prepared from p-type silicon target. Silicon nitride films prepared from p-type silicon target showed higher tendency to distribute uniformly over the substrate's surface. On the other hand, silicon nitride films prepared from p-type silicon target showed higher hardness.