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Diamond Thermal Conductivity: A New Era in Chip Cooling

(spectrum.ieee.org)
200 points rbanffy | 2 comments | 21 Oct 25 11:16 UTC | HN request time: 0s | source
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wpollock ◴[21 Oct 25 16:03 UTC] No.45657461[source]▶
> There are hurdles still to overcome. In particular, we still have to figure out a way to make the top of our diamond coatings atomically flat.

Not sure I understand this. Is this a requirement for real-world use? What happens if the outside of the coating isn't atomically flat? What makes this hard to do?

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1. deepnotderp ◴[21 Oct 25 22:01 UTC] No.45662281[source]▶
It’s difficult to cmp diamond is the issue I’d assume
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2. FaradayRotation ◴[21 Oct 25 22:42 UTC] No.45662664[source]▶
This. A quick scan of the wikipedia page for diamond material properties suggests you are very correct. It appears very chemically inert, with some outstanding exceptions: "Resistant to acids, but dissolves irreversibly in hot steel"

https://en.wikipedia.org/wiki/Material_properties_of_diamond

Also, removed/liberated particles of Diamond from the workpiece which failed to fully chemically dissolve into the slurry would then contribute to the abrasive in the slurry. If the slurry abrasive was not also diamond, then that could lead to some serious scratch/gouging of the work surface.

Perhaps not insurmountable, but wow, that sounds like a stiff challenge, especially when accounting for cost.

I wonder if diamond would be machinable with a dry (plasma) etch instead? I am purely speculating here, this is far out of my wheelhouse. But SiO2 is already very chemically inert (though considerably softer vs diamond), but manufacturers regularly dry etch it.