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Dielectric plating/coating of aluminum and/or copper with "decent" tribological/wear properties

I am a supplier for electronic test devices. I need to conformally coat a conductive or semi-conductive workpiece (a plate of ~1 mm thickness with tens to hundreds of thru holes of roughly 1 mm diameter). The material will be copper, aluminum, or possibly silicon. I need a coating that will be "mildly" electrically insulative (breakdown of ~1000 V/m with resistivity of 1e-7 Ohm-m) but have "decent" wear/tribology properties. I realize "decent" is a weak description, but I could best describe it as something like a spring in a click-pen--it will see some interaction with neighboring elements, but not "too much", just need to keep the workpiece electrically isolated from this level of mechanical interaction. I have looked at atomic layer deposition and PVD of ZrN and diamond-like carbon...the catch is that I am trying to plate thru-holes and the PVD processes don't seem to give me the conformality that I need. I need coating thickness on the order of 10 microns ± 3 microns. I also am most concerned with the electrically insulative properties on the barrel of the holes, not so much of the surfaces "perpendicular" to the holes if that makes sense.

Andrew McFarland
Engineer - San Ramon, California, USA
November 9, 2011