Attention Dead Micron D9 Owners

[saaya]

there are different packaging techniques for every silicon chip out there, memory, cpu, chipset, gpu etc...

every chip is usually so tiny that you can NOT directly put it on the pcb of the mainboard, memory module, vga etc... so you need an extra layer in between. so you have the silicon die that is connected to a tiny pcb, which has relatively large solder balls on the bottom, which can then be connected to the large pcb. to protect the silicon chip many packaging techniques submerge it in some sort of black ceramic, which is what we all know memory chips as. small black squares. well the actual chip sits inside there. cpus used to be submerged in ceramics as well, so were chipsets and gpus... but the heat properties of the ceramic arent that good, so the hotter a chip runs, the more it makes sense to have direct contact to the silicon die.

here are the main packaging techniques im aware of:

• there are actually silicon chips that can directly be soldered to the large pcb (uncommon as those solder balls are relatively large and a chip usually needs a lot more pins per surface than it can get with those relatively large solder balls)
• there are silicon chips that have tiny bga balls on the bottom, which touch a tiny pcb, which has normal bga balls on the bottom which then sits on the main pcb.
• there are silicon chips that are wire "bonded" to the tiny pcb which is then soldered onto the memory pcb.

the latter is the original technique and the most common one for memory chips.
then there are variations of that technique:

• you can solder the wires on the silicon chip and solder them onto the tiny memory chip pcb
• you can solder the wires onto the silicon chip and then basically smash the cold wire onto the tiny memory chip pcb and pretty much bend it on the contact pad
• you can smash the wires onto the silicon chip and smash them onto the tiny memory chip pcb.

the wires are tiny, so you dont need that much force to smash the wires onto the contact points on the silicon and on the pcb contact points. i dont remember which technique micron uses, but it involves smashing the wire onto a contact point on either the silicon on pcb side.
it sounds like both heating or cooling the chips can somehow fix wire bonding issues... how exactly im not sure... the metal bonds should stretch or shrink most in the whole package, the silicon and cermamic shouldnt stretch ot shrink as an effect of the temperature.
so it almost sounds like the wires came lose or lost good contact at least, and changing the temperature will rub the metal wires against the contact pads or at least increase the pressure of the wires against the contact pads, and thus improce the contact again...

very interesting!