Slowing down the Rhythm - Enhancing Tool Efficiency by Low Frequency Powered Processes for Dual Magnetron Sputtering

摘要

State-of-the-art industrial sputter processes are either DC or AC-MF powered. It is known that with a straight DC discharge a long-term stable processes cannot be established for sputtering of dielectrics due to the disappearing anode effect and sometimes excessive arcing. These difficulties in reactive sputtering can be overcome by using AC-MF processes [1]. On the other hand it is also known, that DC processes are characterized by higher deposition rates than AC-MF processes, while at the same time with DC sputtering the heat load on the substrate is remarkably lower compared to AC-MF sputtering [2]. Recent developments have made bipolar power supplies available on the market offering the opportunity to freely adjust the frequency over a wide range. Thus it is now possible to establish novel low frequency powered processes which combine the advantages of conventional MF and DC processes. In this paper, these LF powered processes will be reviewed and compared with conventional MF and DC sputtering. Results for deposited films of metals, TCO and oxides will be discussed as well as new opportunities for optimized configurations and more compact design of roll-to-roll coating systems, which are related to the novel LF powered processes.