Baking chips.

[Keatah]

The internet loves nothing more than stirring the pot and filling your head with useless information, all the while making you spend time doing it.

 

So. Is baking faulty chips to reverse electromigration one of these fads & challenges? Has anyone actually wasted time trying this? Let alone having even a partial success..?

[INTVCruise]

19 minutes ago, Keatah said:

The internet loves nothing more than stirring the pot and filling your head with useless information, all the while making you spend time doing it.

 

So. Is baking faulty chips to reverse electromigration one of these fads & challenges? Has anyone actually wasted time trying this? Let alone having even a partial success..?

I'm pretty sure Adrian's Digital Basement baked about 20 or so Commodore 64 chips in an oven to try and none of the chips were able to be revived. 

[+batari]

I have never revived a bad chip by baking. I have tried with a lot of bad chips I got once, and it made no difference.

 

That is, unless you want to count a batch I got that had a MSL of 3 and was inside a failed dry pack. I had to bake those but for very different reasons.

[Keatah]

I think Arcade Jason was able to recover a Pokey. But overall the ratio seems less than 30%.

[+Stephen Moss]

On 2/14/2022 at 11:41 PM, Keatah said:

So. Is baking faulty chips to reverse electromigration one of these fads & challenges?

Sounds like the usual load of "I don't know what I am doing so I'll try any old crap at random" which then appears to one one that one occasion and is then publish online as a look at me, I have found the solution to your problems, aren't I great thing.

 

First were the allegedly fixed IC's separated from the PCB or mounted to it, if the latter then it was probably just a bad PCB-IC solder joint that was reflowed if the temperature was high enough and nothing whatsoever to do with electro migration.

 

Second, if you were inclined to try it...

1. I would remove the IC from the PCB, as some capacitor, particular electrolytic don't take kindly to being heated to high temperatures as you could cause the electrolyte to boil.
2. The silicon die of IC's is bonded by thin gold wires to the external connection and are generally soldered, so you need to be very careful. If you heat the IC enough you risk solder melting, causing the bond wires to become disconnected resulting in failure of the IC. Again it was more likely to be a bad die-pin solder join that was reflowed rather than electro migration that revived it and blind luck that it did not disconnect others (a more likely outcome of baking) on that occasion.
3. Probably not a good idea to use your usual oven particular if baking an entire PCB as hazardous chemical could be emitted that you don't want getting into your food the next time you cook.

Finally, unless you can find proof from a reputable source that a faulty chip was opened up and tests performed to prove beyond all doubt that electro migration and only electro migration was the cause of failure and that subsequent baking conclusively revered the electro migration then take all talk about electro migration being the cause of the fault and baking as the solution as total speculation. Also this YouTube video would appear to show that baking as a solution is nonsense.

[john_q_atari]

For those that are curious, this is a relatively straight forward explanation of electromigration:

http://www.synopsys.com/glossary/what-is-electromigration.html

 

The simple application of heat is not going to put all those metal atoms back in the right place.

Edited February 17, 2022 by john_q_atari

[emerson]

I have yet to read the above article on electromigration, but several microchip datasheets will specify the chip can only be exposed to X temperature for X amount of seconds or else damage may result. SMD solder profiles are carefully tuned to, among other reasons, prevent heat damage to semiconductors. Therefore, I conclude that prolonged exposure to excessive heat will likely damage chips.