Time resolved study of the HiPIMS palladium, platinum and gold post-discharge
Résumé
During the last decade, high power impulse magnetron sputtering (HiPIMS) has attracted a widespread interest in the scientific community because of substantial improvements over conventional pulsed direct current magnetron sputtering (DCMS). HiPIMS is utilizing high peak power densities of typically several kilowatts per square centimeter at a low repetition frequency. The specific sputtering regime in HiPIMS mode might allow the production of a dense ionized metallic vapor, which is not the case with pulsed DCMS. Some authors report a ratio of ionized species over 70 % in HiPIMS processes. This ratio, obviously, depends on numerous experimental parameters of the process deposition, but also of the sputtered target nature.
This study focuses on the observation of the HiPIMS post-discharges using three different sputtering targets (Pd, Pt, Au) and different noble gases (Ne, Ar, Kr, Xe). The diagnosis of post-discharge is mainly achieved by the combined use of a mass spectrometer (MS), a retarded field energy analyzer (RFEA) and a polarized quartz crystal balance (PQB). The ion/neutral ratio is given for all target materials and plasma gases. In fine, part of time resolved ion energy distribution functions (IEDFs) is also given for multiple discharge conditions