Where USB Memory Sticks are Born (2013)

Posted by jacquesm 6 days ago

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Comments

Comment by userbinator 3 days ago

(2013) but I think 13 years later there might still be such operations in existence, although using much worse TLC/QLC NAND.

The Intel/Micron L73A die shown there is 25nm MLC rated for 3K cycles, and was already the bottom tier of the time; these days, good TLC is around 1.5-3K, and bottom-tier QLC is rated at less than 1K cycles (600-800 seems typical). (For comparison, there is also the M73A of roughly the same era, which is SLC rated for 60K cycles.)

Comment by derefr 3 days ago

> The lady is using some sort of tool made out of hand-cut bamboo. I still haven’t figured out exactly how they work, but every time I’ve seen this process they are using what looks like a modified chopstick to place the chips on the board. My best guess is that the bamboo sticks have just the right surface energy to adhere to the silicon die, such that silicon will stick to the tip of the bamboo rod.

I wonder how such a tool differs from the wax-pencil placer tools used in diamond painting, or the silicone-cone-tip tools used in "bedazzling" (rhinestone placing).

Comment by alnwlsn 3 days ago

I wonder if they aren't sticking the die to the end of their finger, then using the bamboo stick to poke it off and get it into final position. That's probably how I would attempt it given those materials.

Comment by thenthenthen 3 days ago

This is what stood out for me as well. I am really interested in ‘endemic tools’.

Comment by alnwlsn 3 days ago

I occasionally do some microsoldering, and I'll reach for a wood toothpick when I need something that's absolutely non-magnetic, soft enough to not scratch things, does not conduct much heat, or is not wetted by solder. At those scales, stainless steel tweezers are quite strong magnets. Sometimes you just need a tiny stick to poke a component off the end of the tweezers.

If you need a stick that's sticky instead, you can wet the end with something - water, flux, hopefully not your own saliva. Then expose it to some heat from the hot air gun, and the liquid will evaporate and unstick the thing you picked up.

Comment by deepsun 3 days ago

I thought everyone used ceramic tweezers for that.

Comment by amelius 3 days ago

The wirebonding process is interesting but not nearly as interesting as how the chip itself is made.

Comment by Smalltalker-80 3 days ago

Indeed, they missed the tiny part of creating the actual memory...