Diamond based Heatsinks (Highest Thermal Conductivity Available!)

[rayman2k2]

i think we'll see gold heatsinks before we get diamond ones.


and afaik gold's thermal conductivity > diamond's.

 

[zer0signal667]

before I go home, I just wanted to mention that there are quite a few papers on using emical-vapor-deposited (CVD) diamond as an interface for Laser LEDs. I also remember seeing an article concerning the use of diamond as the packaging substrate for multi-chip packages in order to better spread heat around.

Ah here it is http://www.red-river.com/Publicatio...f a Miniaturized Commercial Supercomputer.pdf

look at the bottom of page 2, showing the difference between an aluminum packaging and the diamond packaging. Isn't is pretty?

*ahhh* *oooh* *uuuh*

That's a contrast between AluminAAAA (a ceramic, bad thermal conductivity, not to be confused with aluminUM metal) and diamond packaging.

 

[zer0signal667]

i think we'll see gold heatsinks before we get diamond ones.


and afaik gold's thermal conductivity > diamond's.

Not in theory...
gold is a poorer conductor than copper, by the way.

 

[$BangforThe$]

I followed 1 such thread were the diamonds were pulverized and mixed to create a thermal compound all was seemingly going well and the poster just quit posting it was interesting

 

[zer0signal667]

I followed 1 such thread were the diamonds were pulverized and mixed to create a thermal compound all was seemingly going well and the poster just quit posting it was interesting

Just vanished, huh...? Was it John Titor?

Got a link? sounds interesting

 

[wetware_interface]

Diamond powder in a metal matrix would be more likely to work than in a ceramic matrix, however I don't know if it would end up being better or worse than just pure metal. You'd have to think about things like interface quality which is never perfect and hence will degrade thermal conductivity.
Also, diamond is metastable, but will remain in diamond form at CPU temperatures so thermal degradation is not an issue. I don't understand what you mean about the suspension - diamond is much less dense than silver, which is suspended in AS products. Make a thick enough goop and it won't be a problem.

actually diamonds are continually deteriorating once you remove them from the pressure of their natural enviornment. the more you heat them the faster they deteriorate. at cpu operating temperatures after 1-2 years you would need to remove the thermal paste and reapply as the surface area would have a carbonized layer preventing any thermal transfer benefit you realized. also a thermal paste based on diamonds in suspension would be less effective than just using a pile of fine ground diamond dust as a center layer and then sealing from the outside edge to retain it using old fashioned thermal compound as a restrainer.


and artic silver doesn't have silver in it.it hgas a "silvered finish" polysynthetic in it. basically the crap silver film powder coating you see on one way plastic sheeting suspended in thermal paste. not silver.

as to thickness of goop.
you want a finer grain in the goop material than the grain in your conductive material your embedding in the goop. the goop acts as a suspension device, i.e. it holds the product doing the actual thermal transfer and prevents breakdown or loss without adversly affecting the performance of thermal material too much. the finer the goop material is the more it sits below the surface level of the transfer material and the transfer material becomes more effective as it can contact itself more effectively and both mating surfaces you want heat to be conducted between. viscosity is another matter and is only relevant in dealing with the paste being able to stay put for long periods after application.

as to why not metal?
if you are using diamond you are doing it to acheive transfer of heat that is beyond what metals can deal with effectively. we aren't talking about the need to overclock a p4 to 4 ghz diamond would be used to go way beyond 250 watts of heat. otherwise why use it at all. a ceramic would be able to withstand those temperatures without breaking down or expanding or contracting as metal would. meatl at high temperatures expands. as it does it would crack at the points where it is supending the diamond matrix as the diamonds wouldn't expand. also as it expands it pushes itself and the diamond matrix away from the surface you'd be trying to cool and in the process would have worse thermal transfer abilities.

if you just wanna cool a 4ghz cpu what's the point of diamond? just use a phase change or extreme water block with a huge loop and radiator. diamond would be for beyond extreme overclocks.

 

[zer0signal667]

actually diamonds are continually deteriorating once you remove them from the pressure of their natural enviornment. the more you heat them the faster they deteriorate. at cpu operating temperatures after 1-2 years you would need to remove the thermal paste and reapply as the surface area would have a carbonized layer preventing any thermal transfer benefit you realized. also a thermal paste based on diamonds in suspension would be less effective than just using a pile of fine ground diamond dust as a center layer and then sealing from the outside edge to retain it using old fashioned thermal compound as a restrainer.

I can't argue against your thermal degradation statement, but I'll request some evidence to back it up. As for a pile diamond dust working better than dust suspended in fluid - no... the pile is essentially a diamond-air composite. Air is a bad thermal conductor (in comparison to, say, silicone grease for obvious reasons). Fill in those spaces with silicone grease and you'll have something that not only performs better technically, but can actually be used practically.

and artic silver doesn't have silver in it.it hgas a "silvered finish" polysynthetic in it. basically the crap silver film powder coating you see on one way plastic sheeting suspended in thermal paste. not silver.

I'm not sure what "silvered finish" polysynthetic is, however AS claims:

Contains 99.9% pure silver:
Arctic Silver 5 uses three unique shapes and sizes of pure silver particles to maximize particle-to-particle contact area and thermal transfer.

as to thickness of goop.
you want a finer grain in the goop material than the grain in your conductive material your embedding in the goop. the goop acts as a suspension device, i.e. it holds the product doing the actual thermal transfer and prevents breakdown or loss without adversly affecting the performance of thermal material too much. the finer the goop material is the more it sits below the surface level of the transfer material and the transfer material becomes more effective as it can contact itself more effectively and both mating surfaces you want heat to be conducted between. viscosity is another matter and is only relevant in dealing with the paste being able to stay put for long periods after application.

If you're referring to the fluid as "goop", then it does not have a grain size...
And it sounds to me like you're suggesting the fluid separates and moves outside of the boundaries of the system (boundaries being either mating surface). If it's "below the surface level", does that mean it has somehow moved through metal?

as to why not metal?
if you are using diamond you are doing it to acheive transfer of heat that is beyond what metals can deal with effectively. we aren't talking about the need to overclock a p4 to 4 ghz diamond would be used to go way beyond 250 watts of heat. otherwise why use it at all. a ceramic would be able to withstand those temperatures without breaking down or expanding or contracting as metal would. meatl at high temperatures expands. as it does it would crack at the points where it is supending the diamond matrix as the diamonds wouldn't expand. also as it expands it pushes itself and the diamond matrix away from the surface you'd be trying to cool and in the process would have worse thermal transfer abilities.

Keep in mind we're switching tracks from thermal paste to solid heat transfer devices (heatsinks) here... You're making huge generalizations. Don't you think that engineers are aware of such properties and able to design products accordingly? Diamond-reinforced metal matrix composite is not some fantasy material that I thought up in my head. Nor are the numerous other ceramic-reinforced metal-, polymer-, and ceramic-matrix composites.

if you just wanna cool a 4ghz cpu what's the point of diamond? just use a phase change or extreme water block with a huge loop and radiator. diamond would be for beyond extreme overclocks.

That's what I said waaaaay up there ^^^^ Diamond is not a practical heatsink material right now.

 

[Ice Czar]

As for a pile diamond dust working better than dust suspended in fluid - no... the pile is essentially a diamond-air composite. Air is a bad thermal conductor (in comparison to, say, silicone grease for obvious reasons). .

Its the molecular structure of carbon that makes it such a great heat transfer material
as mentioned any dicontinuity will have serious degradation

Diamond Carbon Matrix

Diamonds are passe these days, it will be Carbon Nanotubes that recieve the lion's share of development

http://nanotechwire.com/news.asp?nid=2654
but they are so closely related that its a matter of semantics almost
they are in effect little diamond pipes or chimneys

Carbon Nanotube

grown diamond substrates such as CVD (chemical vapor deposition)
is already quite common
http://www.anatechltd.com/Diamond_Coating/default.html
at least in some applications, but again suffers from any discontinuity of the matrix
its still a matter of transfering from a point source to a far larger interface without any discontinuity and nanotubes offer a far better fabrication potential than any "diamond"

 

[zer0signal667]

Ice Czar - the picture you have up there shows the structure of carbon in its graphitic form. The diamond crystal structure is a bit more complicated
Check this link for the run-down. I understand that physical discontinuities create a discontinuous path for heat transfer, such is the case with all materials... What I was saying is that it's better to fill those spaces with something other than air.

 

[masher]

De Beers could care less about the industrial diamond market. They're only out to make your wife believe that blood-soaked hunks of carbon from the earth mined by poor Africans working in slave-like conditions are the representation of true love.

The bleeding heart crap is far off base. I've been to South Africa, have you? A job at Bultfontein or Kimberley puts a mine worker far above the average standard of living in the nation, and de Beers is never short of applicants. Talk of "slave labor" is sophomoric nonsense.

 

[Ice Czar]

Ice Czar - the picture you have up there shows the structure of carbon in its graphitic form. The diamond crystal structure is a bit more complicated
Check this link for the run-down. I understand that physical discontinuities create a discontinuous path for heat transfer, such is the case with all materials... What I was saying is that it's better to fill those spaces with something other than air.

http://www.nyu.edu/pages/mathmol/library/carbon/

Graphite

molecular structures are best viewed "in the round"
and are often modeled differently I do like your link however
my post was in support of yours, well with some additional rambling
air certainly qualifies as a discontinuity

 

[Ice Czar]

The bleeding heart crap is far off base. I've been to South Africa, have you? A job at Bultfontein or Kimberley puts a mine worker far above the average standard of living in the nation, and de Beers is never short of applicants. Talk of "slave labor" is sophomoric nonsense.

thats a rather brief view of history, there is little doubt the Kimberlite deposits in South Africa were the primary financial means to impose and maintain apartheid,
South Africa was after all orignally a colony, thus de facto taken by force.

But a more recent example is close at hand.

While you may find his argument sophomoric, DeBeers didn't when negotiating with the post Apartheid government.
And more importantly is in spin control over its buying of conflict diamonds on the open market.
But enough "off topic" posting there is a soap box for this type of discussion in the subscriber section

 

[zer0signal667]

http://www.nyu.edu/pages/mathmol/library/carbon/

Graphite

molecular structures are best viewed "in the round"
and are often modeled differently I do like your link however
my post was in support of yours, well with some additional rambling
air certainly qualifies as a discontinuity

Ahh, on closer inspection I can sort of twist those bonds around in the 3D space in my mind... (in your first posted picture) At first it looked like a stack of graphite layers, my apologies
On an interesting note, silicon shares the same crystal structure as diamond. I wonder if there's something about this structure that makes the materials good candidates for semiconductor fabrication.

 

[Ice Czar]

http://www.geek.com/news/geeknews/2003Jan/bch20030103017989.htm

One of the more intriguing prospects in the semiconductor world is diamond. Diamond has many properties that are superior to silicon. Diamond has a higher bandgap than silicon, can tolerate higher temperatures, and has the potential to form transistors that switch faster than silicon. Ralph Merkle notes that:

"Diamond excels in its electronic properties. Fundamentally, it lets us move charge around much faster before things stop working. [snip] ... diamond transistors can operate at much higher temperatures because diamond has a larger "bandgap" than other materials (particularly silicon) ... [snip] ... Because diamond has a wider bandgap, it shorts out at a proportionally higher temperature than silicon.

Diamond also has greater thermal conductivity, which lets us move heat out of a diamond transistor more quickly to prevent it from getting too hot.
... [snip]
Finally, electrons (and holes) move with different speeds through different materials, even when the electric field is the same. Again, electrons and holes in diamond move faster than in silicon.

Because diamond transistors can be hotter, are more easily cooled, can tolerate higher voltages before breaking down, and electrons move more easily in them; they make better transistors than other materials. Diamond would be ideal for electronic devices if only we could manufacture it inexpensively and with precisely the desired structure.

Merkle's arguments are supported by the fact that the Japanese Government wants to create diamond-based microchips. The government-industry venture will endeavor to create power electronics and flat-panel displays using diamond transistors. If this project is to succeed, the researchers will need to find a way to inexpensively mass-produce diamond wafers, and also discover a means to effectively dope diamond substrates.

3 years old now

http://www.wired.com/wired/archive/11.09/diamond.html
http://www.geek.com/news/geeknews/2003Aug/gee20030827021485.htm

While large scale production is easily a decade or more in the future

only seven or so to go

 

[masher]

thats a rather brief view of history, there is little doubt the Kimberlite deposits in South Africa were the primary financial means to impose and maintain apartheid

You are quite wrong. The British invasion of the Boer republics was motivated far more by the gold discoveries in the 1880s than by the earlier finds at Kimberley, and even today South Africa remains the world's largest producer of gold and platinum.

As for diamonds being the "primary means" of enforcing apartheid, from WW2 onward mining of all natural resources combined was no longer the largest sector of the economy. Diamonds alone were a small fraction of the total. Today, South Africa's GDP is nearly $500 billion. Diamonds comprise a little more than $1B of that, or 1/4 of one percent of total economic output.

South Africa was after all orignally a colony, thus de facto taken by force.

I defy you to name a single spot of land anywhere in the world that hasn't been taken and retaken by force uncounted times through history.

 

[Ice Czar]

as I said this is offtopic

Id be happy to discuss the finer points of colonization in the SoapBox

 

[Hvatum]

The bleeding heart crap is far off base. I've been to South Africa, have you? A job at Bultfontein or Kimberley puts a mine worker far above the average standard of living in the nation, and de Beers is never short of applicants. Talk of "slave labor" is sophomoric nonsense.

Ever heard of Sierra Leone? Do you read newspapers?

No matter what the Diamond industry says conflict diamonds are in the supply line, there's simply far too much financial incentive there. No testing process is one hundred percent foolproof. Even if there were it's far too expensive to test every diamond.