2D Tin Could Be The Next Supermaterial And A Substitute For Silicon

Bedlam

amraks
This technology will be great.

This could solve BGA(ball graph array) problems, PS5 will have this tech if it does solve it and the next Xbox what ever they will call it I don't know, they kinda muddled it up.

BGA chips on PCB BGA pads are prone to failure after overheating, after the heat becomes to much and liquefies the solder spheres under the BGA chip. After awhile time over time there is usually 1 - 10est connections from the BGA not making contact with PCB BGA pads, there for making a device not function as intended switching it into error mode.

Not at all.

First off, it's ball grid array. Second, when you reflow the thing onto the board to begin with, you intentionally melt the balls so that they form a solder joint under there. The chip cannot possibly become hot enough in normal operation (short of catastrophic failure) to reflow the balls again.

Heat stress can cause badly reflowed BGA balls to crack loose if you've got really crappy joints and/or badly matched TCA between the chip's substrate and the PCB. But not if it's done right.

Finally, this technology won't do squat for chip mounting technology anyway. The 2D tin technique is applicable to interconnections on the silicon itself. Not the packaging and external connections.

eta: we use BGA and QFN on every military and aerospace design we do. It holds up to insane temp ranges and G forces if done right.

edit on 24-11-2013 by Bedlam because: (no reason given)

Was half asleep while writing that but anyway.
Ball Grid Array.

Well thats good still be in business fixing ps3, x's gfx cards, laptops, until the next advancement lol.

May I ask how big the solder spheres are they use in satelites and military are?
what ratio are the spheres like tin 80%, lead 20% blah blah kinda hoo haa?

amraks

May I ask how big the solder spheres are they use in satelites and military are?
what ratio are the spheres like tin 80%, lead 20% blah blah kinda hoo haa?

Depends on the part. Some are down to 0.12mm.

Nah, no lead in the wonderful new world of ROHS. It's tin-silver for most of them.

We went through a period when our local contract mfr was having balls crack loose under G force and shock testing, we bought a $100K ersascope so we could look under there and see what was going on, did a lot of materials analysis and found the issues. If you put down a BGA properly, they don't just pop loose whilst playing Call of Duty on the desk top. Nor do the chips get hot enough to melt the solder again.

There are, however a lot of ways to do it WRONG, and then they'll come loose if they were ever down to begin with. A lot of times what you've got are the balls resting on the pads but no joint ever formed. The balls on the outside reflow and the ones in the middle don't, particularly power pins, and with enough thermal cycles they lose that pressure contact with the pad, or the pad oxidizes a bit and Bob's your uncle.