Effect of Bias Voltage on Mechanical Properties of HiPIMS/RFMS Cosputtered Zr-Si-N Films

Materials (Basel). 2019 Aug 21;12(17):2658. doi: 10.3390/ma12172658.

Abstract

Zr-Si-N films with atomic ratios of N/(Zr + Si) of 0.54-0.82 were fabricated through high-power impulse magnetron sputtering (HiPIMS)-radio-frequency magnetron sputtering (RFMS) cosputtering by applying an average HiPIMS power of 300 W on the Zr target, various RF power levels on the Si target, and negative bias voltage levels of 0-150 V connected to the substrate holder. Applying a negative bias voltage on substrates enhanced the ion bombardment effect, which affected the chemical compositions, mechanical properties, and residual stress of the Zr-Si-N films. The results indicated that Zr-Si-N films with Si content ranging from 1.4 to 6.3 atom % exhibited a high hardness level of 33.2-34.6 GPa accompanied with a compressive stress of 4.3-6.4 GPa, an H/E* level of 0.080-0.107, an H3/E*2 level of 0.21-0.39 GPa, and an elastic recovery of 62-72%.

Keywords: H/E*; H3/E*2; HiPIMS; RFMS; bias voltage; elastic recovery; mechanical properties; residual stress.