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3D3DBroken sputtering target.
Description supplied by the source:
This is a fractured piece of germanium from a sputtering target that was melted, machined, polished, put into service, and then apparently broken during use after not too long. The silver-looking material on the back is, in fact, silver in an epoxy matrix. Depending on the particular process being used, some sputtering systems use the target as an anode, and thus they must be conductive. For metal targets, indium or gallium/indium eutectic is commonly used to 'glue' the target to its backing plate and provide a good electrical connection. However, those two only 'infiltrate' and glue metal to metal effectively, so epoxy with dispersed silver particles is generally used for targets made of intrinsic semiconductors like germanium or any number of other uses where indium or liquid metal alloy would be inappropriate for whatever reason. However, for sputter systems or anything else that will be used in a high vacuum environment, one has to be very careful about what materials are employed, especially with organic glues and gaskets, because many materials are porous to gases or will outgas themselves at .00000000001 atmospheres.
Source: Ethan Currens
Contributor: Ethan Currens
Acquired: 21 March, 2008
Text Updated: 21 March, 2008
Price: Anonymous
Size: 1.5"
Purity: 99.999%
Germanium