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aurareturn 2 days ago

Chip density increase is slowing down. Since N10, density scaling has been 60-80%. N3 to N2 is only 20%. And now N2 to A14 is also only 20%.

davnicwil 5 hours ago | parent | next [-]

20% growth then 20% again still seems pretty good to me though. I guess compounded that is a 44% increase N3 to A14 which also starts to look much better if you zoom out a bit. I mean 44% more density since a few years ago seems, if not massive, not insignificant, like you will definitely notice it.

chorsestudios 4 hours ago | parent | prev | next [-]

Yes but considering N10 was fabricated with DUV lithography right before the shift to EUV I'm not sure how fair that comparison is. That being said the density scaling of N10 nodes compared to predecessors using the same lithography technique was much higher than we have seen since with the EUV nodes. Density scaling is the most meaningful comparison metric, but it doesn't take into account additional technology developments.

osnium123 2 days ago | parent | prev | next [-]

Is the increase in wafer cost higher than the density increase? If so, that means that the cost per transistor is also going up.

xenadu02 3 hours ago | parent | next [-]

If we exclude short-term shortages then no. The cost to make a wafer hasn't really changed. Larger wafers improved costs but that's about it AFAIK.

Feature sizes have been shrinking unevenly for two decades now combined with the overall slowdown in improvements. Transistors themselves are FinFET geometry and something like 15-30 atoms thick and maybe 80-100 across. There ain't much juice left to squeeze in terms of size but perhaps we'll figure out how to reduce leakage (heat).

Physics hates the very large and the very small. The large get the tyranny of volume scaling + general relativity. The small have their entire concept of reality smashed by quantum mechanics.

aurareturn 2 days ago | parent | prev [-]

It's hard to tell because AI has pushed up costs. IE. Chip fab margins are increasing.

But generally, I think it's even or increasing $/transistor for each node. I'd guess that A14 would have been 20% more expensive than N2 regardless or AI or not.

It probably is still worth it because you're also getting 20-30% better power efficiency - which is a big deal for data center chips.

georgeburdell a day ago | parent | prev | next [-]

A lot of that is the lack of SRAM scaling. There’s still quite a bit of improvements in the back end (metal traces). That aside, if foundries adopted say a 1T-1C SRAM we’d see a pretty rapid density doubling

smallmancontrov 7 hours ago | parent | next [-]

Is 1T1C SRAM a technological thing or does it mean "persuade designers to use DRAM in the many cases where the retention contract could be timeboxed with a bit of extra thought and cross-team haggling"?

the8472 6 hours ago | parent | prev | next [-]

MRAM is 1T, non-volatile and supposedly has nanosecond-scale write times so it naively seems like it'd be an ideal SRAM replacement. But I guess shrinking MTJ is more difficult than other components or there are some other limitations.

tliltocatl 6 hours ago | parent | prev [-]

> 1T-1C SRAM

Aka eDRAM? It was a thing back on 14nm node, but AFAIR not so much anymore. The 1C part is hard to get right in a way that is compatible with a logic process.

to11mtm 4 hours ago | parent [-]

It gets confusing...

eDRAM isn't the same as 1T-SRAM, which isn't quite the same as 1T-1C SRAM...

But overall they run into the same problems that you mention; it's just too hard to get a capacitor in play.

There is Zeno Semi's Bi-SRAM, buuuut it hasn't seemed to catch on for one reason or another.

kvemkon 4 hours ago | parent | prev [-]

Between N2 and A14 should sit A16.