Reactive High Power Impulse Magnetron Sputtering
|Coordinator||KUNGLIGA TEKNISKA HÖGSKOLAN - KTH EES|
|Funding from Vinnova||SEK 3 264 470|
|Project duration||January 2015 - August 2018|
Purpose and goal
High power impulse magnetron sputtering (HiPIMS) is a thin film deposition method that has significant potential in industrial application. We demonstrated that Ohmic heating of the electrons maintains the HiPIMS discharge an sheath acceleration of secondary electrons plays in some cases a minor role. The high discharge currents observed in the HiPIMS discharge can only be realized through a recycling processes, either due to ions of the working gas or the ions of the sputtered material or both. The type of the recycled ion depends on the self sputter yield of the target material.
Expected results and effects
The low deposition of the HiPIMS process has been the major drawback for the use of this technique in industrial application. Through modeling and experiments we identified the main cause of the low deposition rate. The high discharge current is mainly due to ion recycling, and thus much of the sputtered material is not deposited on the substrate.
Planned approach and implementation
One of the key discoveries is that for reactive HiPIMS deposition a significant part of the discharge current at the cathode target is due to the ions of the working gas. The question arises if the high currents realized are necessary ? Can we develop the high plasma density needed without these high discharge currents ? Can we manipulate the confining magnetic field in such a way that less of the ions of the sputtered material returns to the cathode target ? These are some of the many technical issues that still remain.