That looks almost identical to some damage I had on a water block and gpu die.
Photos from the problem that I had that I think was created by some chunky diamond crystals were in my IC Diamond.
Pit in block
http://minidriven.com/BlacknBlueforIB/ICDIAMONDDUSTPIT/ICDiamondPitproblem.jpg
Mark on die with some micro scratches.
http://minidriven.com/BlacknBlueforIB/ICDIAMONDDUSTPIT/markondie.jpg
I am 99% convinced that some of these tubes of IC Diamond have large chunks of diamond crap that does this.
I have figure out a way to apply IC Diamond and not have to use high pressure. a little smudge of it with rubbing alcohol smoothed o ut over die.. .Super thin. I think doing it like this helps ensure no diamond nuggets are present.
Sorry for the long pause here we have been distracted with the commercial end of the business
The diamond we buy for our compound is purchased from one of the largest diamond suppliers in the country, the same sources and sizes that are used for optical lapping.
The diamond we buy is commonly referred to in the biz as a flour.Here are some pictures posted as IC Diamond scratches magnified 250% it is no big deal to analyze "scratches" which can only be made a certain width/depth by an established particle size, the fact that they represent a particle size 10X+ times the diamond component in our compound should be noted. Any suggested idea particles are larger than this shows a lack of understanding of the screening process as you will not find 1200 grit sandpaper peppered/contaminated with 150 grit sized particles and especially in mission critical optical components like lasers you will not see errantly large particles. We purchase only the highest quality and pay through the nose for it.
To draw a contrast for you I am privy to a competitors processing technique in which the paste is mixed in paint mixers, in a block building, with unfiltered air.
We are not Yahoos or hillbilly's, we contract our mixing and the people that do it, do it in a sterile air filtered environment on million dollar machines that heat the compound and mix it in a vacuum to prevent any air being folded into the compound. In addition prior to mixing our contract manufacturer performs QC testing to validate materials received meet specified material requirements.
The containers we receive from our contract mixer are unopened and tubes are filled directly from the sealed container through the syringe tip. Our processing and quality control are state of the art.
We do pay attention and we do collect reports of supposed scratching and they are analyzed and found with out merit.
When researching a problem you look for a commonality between samples.
Below sample was recently circulated and claimed the belt sanded look was due to the sink sitting stationary on the IHS and that he was excruciating careful cleaning off the compound. Happens to be a different grit size/finish, varying grit sizes? Note the white lettering overlaying scratches. I honestly do not know the question to this - does Intel do white ink print ID on nickel plated IHS's?
So here is a third one with a North South orientation, this "clear" picture has the addition of a circular scratch finish - This was noted as a lapped IHS. The circular marks are the same as the N/S in size which indicates it was done with the same abrasive medium, both 10X + any particle size in IC Diamond.
So a third with a another different finish - So where is the connection? it's not there.
The images below were final lap with IC Diamond, an intentional abrasion with ICD with no visible scratching, that's it, nada, none, nowhere to be seen, nonexistent, mort, deceased, no longer with us, the parrot is dead. The suggestion is ridiculous and as a point of fact if you applied Colgate toothpaste to that finish it would fog the mirror finish not because it is harder but the toothpaste particle size is larger and but still harder than copper to provide a scale of reference for the posted pictures.
Note I sent the pictures on this thread to our supplier and his response
"estimating the particle size particle necessary to produce that kind of damage as a rough estimate is 50 to 100 times larger than the largest size diamond our process can make"
The fact here is the particle size is on a scale as to be physically impossible to create and scaling the picture and measuring the mark it appears to be too large to even fit through the tip of the syringe and any damage is more likely due to contamination on the install.
