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Package
I (JM) would recommend thermal fracture if you are comfortable with a torch.
Thermal fracture
Procedure
Place package on a temperature resistant surface
Heat package with a propane torch until hot, maybe 5 or 10 seconds
Gently splash or sprinkle water on the package. This should create micro-fractures and make it easy to shear
Shear the package open by applying light force. Unlike a non-fractured package this should be possible using simple pairs of pliers or by hand
Tips:
Chip does not have to be heated until red or white hot. Heating this high increases risk to damage the die from glass reflowing as well as general thermal stress
Do not throw the chip into liquid or move it all while it is hot. This can cause the glass to shift and get onto the die
PDIPs should be supported (ie with a block of metal) as the leadframe will become very weak
If it does not shear open the first time try again. Consider increasing heat, pressure, or simply do more runs
Advantages:
Disadvantages:
Thermal shock can potentially also break die
High temperatures can warp die
The die is exposed but still in the package
Chip before (both identical):
No images found.
One of these was thrown into water and the other had water dripped on it. Comparison:
Dunked chip close-up:
Dripped on chip close-up:
The motion of throwing the chip into the water caused the glass to flow and stick to the die. When the top was sheared off some of the die snapped off as a result. Additionally, it isn't as regular from moving around and so didn't break nearly as cleanly.
Lift-off
Requires some form of torch. Heat up and pry up. Be careful not to let molten glass land on the IC. The best way to avoid this is to lift straight up and let it cool a bit before moving off to the side.
Shearing
The glass tends to be much weaker than the ceramic. Therefore, its possible to shear a chip open by moving the top and bottom half in different directions.
Procedure
Place bottom half of package into vice. It may be desirable to put a metal space in between the pins to keep pressure more even
Firmly hold the top of the chip and twist. Keep the movement orthogonal to the glass plane
Ideally this would probably be done using a custom fixture to hold the top and apply even and straight force
Tips
Plumbing wrenches work well to hold the chip as their width can be adjusted for even pressure while still holding it tightly
Be careful with long CERDIPs that you don't apply too much torque on an end and snap the chip in half instead of shear it
Advantages
Disadvantages
Throws debris onto die
Can be difficult to effectively grip top half
Can be difficult to tell how much force is required
Unpredictable how it will shear
Grinding
I see no reason why you couldn't grind one open (eg with a Dremel) but it would probably take a long time and would require extensive cleanup after.
Die
This has been a problem area and so the best advice I have is simply don't try to remove the die unless there is a good reason. If someone knows of a good way to remove glass affixed dies I'd be interested. All of these assume the package has already been opened.
Hot pull
Procedure
Surface tension makes simply plucking the die up difficult and so a knife tends to work better. Unfortunately, metal tweezers / knives chip dies and plastic tweezers melt. PTFE does a little better but puts off toxic gas (HF) when heated so its not a good idea.
Crack-n-push
Procedure:
Score one side of the ceramic package well
Heat package strongly
Submerge scored side of package in water. This should cause it to crack roughly along score marks
Re-heat package
Slide die out of open side of well with die
Dissolve
It should be possible to use HF to dissolve the ceramic. Maybe NaOH could work as well?