In an earlier post I mentioned one of the presentations we gave at the 2013 SVC TechCon. The other presentation that our team delivered at the show (presented by Jacques Mateau) regarded another very interesting topic. The paper, High Temperature, Pb-Free, Metallic Sputtering Target Bonding Using Reactive Multilayer Foil, deals with creating high temperature NanoBonds®:
“Metallic bonds provide excellent thermal and electrical conductivity, but are limited by the relatively low melting point of the solder material used, 157°C for indium or 217°C for tin-based alloys. This limits the power input, which in turn limits sputtering rates and final film properties. There is a desire for a higher temperature (>300°C) metallic bonding process that can produce flat, stress-free target assemblies, enabling targets to run at higher temperatures for longer periods of time. We will demonstrate a metallic bonding process using reactive multilayer foils and a high temperature alloy with melting temperatures as high 380°C. We will compare this with traditional Sn-based solders typically used, specifically comparing shear strengths, void analysis, and cross sectional analysis.”
The image shown here is a bond formed with a 98Zn/2Al alloy and 60μm thick NanoFoil®. You can follow the link above to read to paper, and email me if you have any questions or are interested in this process for bonding your sputtering targets.