Dave, are we talking about the same thing ?
yes, the silicon die is MUCH harder than the copper
yes, the edges of the die and of the lettering are quite sharp
yes, transverse movement (with some angularity - the sheared pads ?) will cut into the copper
there could be a ridge, I don't - with a sample of 2 only - have enough data to say
but I have not seen it (yet ?)
but this is not my question; to restate as clearly as I am able:
I do not understand how the compressive load even approximating the AMD spec, or rather well above it, can result in the yielding of the copper in contact with the die face.
yes Ben
I can understand staining/discoloration, I too see that all the time
and it will also vary with the grease used AND the time interval
-> I also see hydraulic edge-cutting from the influx of grease when the closely pressed substrates are separated, sucking in the 'bead' of grease around the die perimeter previously extruded
(this seems to be a characteristic of Cooling Flow having boron nitride particles, and quite a number of mountings are needed before the little erosion channels begin to appear - yes, they lap out gradually, they are real)
no desire for contention here, lets not get all het up
just workin' on 'plastic deformation'
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