Electronic – How to decap a chip to expose the die


Any suggestions to open a surface mount package (TSOP, QFN etc) to expose the die?

Possibilities tried or considered:

  • Split the package using wire cutters – sometimes works and sometimes doesn't
  • Grind the top off with grinder – Some chips have no cavity between the die and the cap.
  • Soak in MEK – I heard this works but haven't tried it.

Why would I want to do this? To photograph for forensics purposes – to look for damage or to get die numbers. I don't expect the part to function afterward. Electronic forensics labs seem to be able to open chips easily but I'm not sure what tools/techniques they use.

Best Answer

Travis Goodspeed has the tutorial: http://travisgoodspeed.blogspot.com/2009/06/cold-labless-hno3-decapping-procedure.html Basically you put the part in a test tube with NO3 and swirl it around and leave it overnight until the encapsulation is dissolved.

Only slightly related, but look through Travis's Flickr stream for a lot of interesting dieshots.