Gas Impermeable coating using High Power Impulse Magnetron Sputtering for High Energy Density Physics Applications*

High Power Impulse Magnetron Sputtering (HiPIMS) is a type of magnetron sputtering technique that is capable of producing high quality, smooth, ultra-dense coatings with superior adhesion to the substrate when compared to conventional DC Magnetron Sputtering (DCMS) technique. In HiPIMS, very short unipolar high power pulses are applied to the sputtering target at low duty cycles. These high power peak pulses result in an intense plasma in front of the magnetron target, which then leads to a high ion fraction of the sputtered material. These energetic ionized sputtered species lead to dense coating. There is huge demand for thin walled, gas impermeable metal capsules for High Energy Density (HED) applications. Currently, conventional DCMS technique is used to produce these thin walled, gas impermeable metal capsules with very low success rate. In this work we are exploring the possibility of using HiPIMS to create dense, gas impermeable capsules. A thorough HiPIMS process optimization for gas impermeability is carried out and the results would be correlated with ion fraction measurement on the substrate using G-QCM (Gridded Quartz Crystal Microbalance), cross-sectional SEM and Krypton leak tests.