why these x-ray photos are different?

Altera_Forum · ‎06-28-2011

I have two part to compare with

Top one is came from Altera japan disty last year

the other one is came from Altera broker this year

the broker part was all factroy sealed pkg and label and other condition was all good

but we just got x-ray photos as follow

and we don't understand why these two parts are different in x-ray

i can't find any explaination about the x-ray image in datesheet

Altera_Forum · ‎06-28-2011

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i can't find any explaination about the x-ray image in datesheet

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Honestly, I won't expect it.

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we don't understand why these two parts are different in x-ray

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Assuming the exposition conditions are exactly the same (are they?), I would consider a different copper weight of the chip carrier PCB ground plane.

Altera_Forum · ‎06-28-2011

Good eyes. The G marking indicates a die shrunk 60nm part, reduction from 6 to 4 layer substrate, and transition from gold to copper interconnect.

http://www.altera.com/literature/pcn/pcn0904.pdf