
Sony develops thermal sheet as good as paste for CPU cooling - ukdm
http://www.geek.com/articles/chips/sony-develops-thermal-sheet-as-good-as-paste-for-cpu-cooling-20120717/
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robomartin
According to this article the claimed thermal resistance is in the order of
0.4-0.2K cm2/W:

[http://news.softpedia.com/news/SONY-Demos-Best-Thermal-
Pad-i...](http://news.softpedia.com/news/SONY-Demos-Best-Thermal-Pad-in-the-
World-281342.shtml)

This is nothing new or earth-shattering as far as I am concerned.

I've been using various thermal interface materials over the years for
interfacing elements needing to be cooled to heat-sinks. These components
range from MOSFETs to LEDs and FPGAs. You can easily achieve thermal
resistance down to 0.11 K cm2/W with form-in-place sheets from companies such
as Fujipoly:

[http://www.fujipoly.com/products/sarcon-thermal-
management-c...](http://www.fujipoly.com/products/sarcon-thermal-management-
components.html)

In some cases the tradeoff is between high thermal conductivity and electrical
conductivity. Where application requirements dictate that the thermal
interface material (TIM) not conduct electricity (high-power LEDs typically
have the thermal slug connected to the anode) you have to select TIMs that
might not contain aluminum or other conductive compounds. In these cases you
might take a thermal conductivity hit.

That said, there are manufacturing techniques for such assembles that enable
the use of electrically-conductive high-thermal-conductivity TIMs while
greatly enhancing the thermal characteristics of the entire assembly. One that
comes to mind is the use of aluminum-clad printed circuit boards as an
intermediate step.

EDIT: Used "thermal conductivity" when the numbers referred to "thermal
resistance"

~~~
vonmoltke
Those numbers are thermal resistance/impedance, not conductivity.

~~~
robomartin
You are right. I tend to think in terms of thermal conductivity, which is not
the same as thermal resistance. Editing post to use proper terminology.

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zxcdw
I think the article tells nothing of importance as it is right now. Since when
has applying thermal paste been messy and requiring trial and error to apply
"correctly"?

These days the thermal load(W/cm²) between the CPU heat spreader(the nickel
alloy(?) coated copper plate on top of the CPU package) and the heatsink base
is so low compared to the thermal load between the CPU core and the CPU heat
spreader, that even if you manage to use ten times more efficient interface
material in between, the actual heat transfer from the CPU core to the
heatsink base wouldn't increase all that much. It's easy to understand, when
you consider that the heat spreader has so much more surface area than the
actual CPU die.

In simplified layman terms, no matter what you put between the CPU and the
heatsink base, you get the same temperature give or take a few degrees
celsius. Of course, the thermal compound starts to matter much more when you
overclock and the thermal load may double or even triple.

I guess new inventions like described in the article are welcome though, but
personally I am no excited at all, regardless of the claimed thermal
conductivity and "real world performance".

~~~
mnicole
> Since when has applying thermal paste been messy and requiring trial and
> error to apply "correctly"?

For people not accustomed to building their own rigs or using thermal paste,
it can have a learning curve. Even having done it before, I had an issue two
months ago where applying a little too much kept me from entering the BIOS.
After some worry I reseated it and it worked fine, but anything that makes the
process of building your own system easier should be a welcome change.

~~~
zxcdw
How is that even possible? How could applying too much material between the
CPU heatspreader and the heatsink keep one from entering BIOS? Even if you
spilt it all over your motherboard and socket, it shouldn't do a damn, as (at
least most?) thermal pastes aren't conductive enough to cause any short-
circuits or other harm.

~~~
mnicole
I couldn't tell you, to be honest. It was originally an issue with the video
card overheating, and I decided to clean and re-organize everything. The
thermal was the only thing I wasn't 100% on, and when I reseated it with less
paste, it worked again.

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vonmoltke
Both articles are rather thin on details about this material. I'm not sure how
much (or if) its better than products that have been in the mil/aero
industry[1] for years. Hopefully it will be easier and cheaper to get ahold of
than the alternatives.

[1] Such as
[http://www.bergquistcompany.com/thermal_materials/sil_pad/si...](http://www.bergquistcompany.com/thermal_materials/sil_pad/sil-
pad-2000_properties.htm)

------
astrodust
Is there a reason the thermal interface of a CPU is a smooth surface and not,
say, a series of thin, deep grooves into which a fan can be slipped in for a
snug fit with a minimal amount of paste? You could easily increase the contact
area ten fold, possibly even more with some clever engineering.

The only down-side would be requiring a fairly precise fit with the heat-sink
where now any old hunk of metal will do.

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vecinu
This is great news and hopefully, they'll bring it to the consumer market too.
Thermal paste is definitely messy and hard to get right.

