Titanium Silicon Nitride Films With Low Silicon Content Deposited via Reactive High-Power Pulsed Sputtering Penning Discharge

Abstract

Reactive high-power pulsed sputtering Penning discharge at a total pressure of 0.7 Pa and an N2 fraction of 20% in gas phase was used to synthesize titanium silicon nitride (TiSiN) films. The content ratio ( $R_{\mathrm {TS}}$ ) of Si in a target containing a Ti component and an Si component was varied from 0% to 15%. The properties of the as-deposited films were compared with those of the films deposited on high-temperature substrates. The chemical compositions and bonding states of the films were investigated via X-ray photoelectron spectroscopy (XPS). Film structure was evaluated via X-ray diffraction (XRD) and transmission electron microscopy-energy dispersive X-ray spectroscopy. Through XPS, the relative content ratio of Si to Ti was found to increase from 0% to ~25% with increasing $R_{\mathrm {TS}}$ , and the nitrogen content ranged between 47.5% and 50% for all films. The grain size of the films deposited at an $R_{\mathrm {TS}}$ lower than 10% was estimated using the XRD peak of the (111) orientation and found to be ~10 nm. The hardness and elastic modulus of the films deposited on high-temperature substrate at an $R_{\mathrm {TS}}$ value of 8% had the highest values of 43 and 360 GPa, respectively.