(no subject)

[randomdreams]

Apparently my style of decapsulating integrated circuits is so different we don't know how to take pictures of the results that show what we want to see. We have damaged chips. When we etch the top off with nitric acid there are spots that won't etch because they're a mixture of metals, epoxy, and silicon. The way I remove the top doesn't leave those spots, so we have to compare the pictures to pictures of a good chip and even then the evidence for damage is subtle: lines that aren't quite straight, for instance. I may have to come up with some way of producing contrast. But, generally, it's extremely successful save for our lack of ability to electrically connect to the die anymore, and we can even manage that with our probe station.

Comments

[darkoshi]

Is the epoxy the substance that looks like black plastic on most chips?

Are there specialized x-ray machines for chips that can show what is under the epoxy, without having to remove it?

On a related note, found this recent article:
http://spectrum.ieee.org/nanoclast/semiconductors/processors/xray-ic-imaging