HiPIMS Deposition Research Articles

Development of HiPIMS deposition technology using a cylindrical target surrounding a substrate for one-piece-flow coating

Development of HiPIMS deposition technology using a cylindrical target surrounding a substrate for one-piece-flow coating

Electrical insulation performance of aluminum oxide layers on metallic substrates – HiPIMS compared to RF-MS

In this evaluation, aluminum oxide layers with thicknesses in the range of 300 nm to 4000 nm are investigated for their electrical insulation capability by measuring the resistance between the substrate and a subsequent conductive layer. The deposition was carried out in a non-reactive RF magnetron sputtering process and in a reactive HiPIMS process, respectively. The substrate materials tested are steel 1.3505 (100Cr6), titanium alloy 3.7164 (Ti6Al4V) and aluminum alloy 3.1645 (AlCuMgPb) with both turned and polished surfaces.Besides resistance measurements, the layers were investigated by SEM and characterized by EDX. During the HiPIMS deposition, the value of the electrical current over the time of one pulse was measured additionally.The comparison of the resistance values showed strong dependencies between the electrical insulation and the substrate materials used, as well as their surface microstructure. Moreover, a deviating insulation performance for the layers deposited by HiPIMS was identified. From the results, a correlation of substrate material, surface microstructure and the corresponding deposition technology is deduced.

Strategy for tuning the average charge state of metal ions incident at the growing film during HIPIMS deposition

Energy and time-dependent mass spectrometry is used to determine the relative number density of singly- and multiply-charged metal-ion fluxes incident at the substrate during high-power pulsed magnetron sputtering (HIPIMS) as a function of the average noble–gas ionization potential. Ti is selected as the sputtering target since the microstructure, phase composition, properties, and stress-state of Ti-based ceramic thin films grown by HIPIMS are known to be strongly dependent on the charge state of Tin+ (n = 1, 2, …) ions incident at the film growth surface. We find that the flux of Tin+ with n > 2 is insignificant; thus, we measure the Ti2+/Ti+ integrated flux ratio JTi2+/JTi+ at the substrate position as a function of the choice of noble gas–Ne, Ar, Kr, Xe, as well as Ne/Ar, Kr/Ar, and Xe/Ar mixtures -- supporting the plasma. We demonstrate that by changing noble–gas mixtures, JTi2+ varies by more than two orders of magnitude with only a small change in JTi+. This allows the ratio JTi2+/JTi+ to be continuously tuned from less than 0.01 with Xe, which has a low first-ionization potential IP1, to 0.62 with Ne which has a high IP1. The value for Xe, IPXe1=12.16eV, is larger than the first ionization potential of Ti, IPTi1=6.85eV, but less than the second Ti ionization potential, IPTi2=13.62eV. For Ne, however, IPNe1=21.63eV is greater than both IPTi1 and IPTi2. Therefore, the high-energy tail of the plasma-electron energy distribution can be systematically adjusted, allowing JTi2+/JTi+ to be controllably varied over a very wide range.