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Love the substack name.
Now we just need another one named worththewirth about the merits of bloated software?
while it all sounds buzzwordy, as an chip industry outsider, none of it seems to make much sense.. is there an ELI5 version of this?
I mean you could paste into ChatGPT:

> Please summarise https://morethanmoore.substack.com/p/the-race-to-2nm-risc-v-...

But this is my _personal_ takeaway: there are companies building (or trying to) Risc-V cores at advanced geometries. That is somewhat unheard of for a rather new and not-yet popular core. This suggests a lot of momentum for it. It's actually a new Japanese company called "Rapidus" that has some major backers and it's working with Tenstorrent (which has had a lot of buzz over the last couple of years). So it's exciting because a new company is entering the ring, from a new country, and they are benefitting Risc-V which is gaining traction.

There is another article on this here: https://www.anandtech.com/show/21281/tenstorrent-licenses-ri...

I'm pretty unclear as to the specifics. Rapidus is wafer processing and packaging; I get that. Is LSTC trying to create a fab directly, a fabless entity more or less directly developing chips, or just trying to be more like China's Big Fund, ie. a central point for disbursement of .gov money targeting domestic semiconductor R&D for other entities to consume as long as they march to the common drum?
https://en.wikipedia.org/wiki/2_nm_process

I'm fascinated by the "Beyond 2nm" section, but don't really understand much of the terminology. If there are any industry experts reading, what sort of chip developments do you think will happen by 2030?

By 2030 we will have progressed to a few atoms per transistor in bulk CMOS, to wafer scale integration [3] and probably replaced most metal wires with free space optics [2]. We will see the first mass-manufactured SFQ [1] and RSFQ [4] superconducting Josephson junctions. Maybe we will see the first carbon nanotubes and superconducting circuits [5].

[1] https://youtu.be/LUFp6sjKbkE?t=21701

[2] https://www.youtube.com/watch?v=7hWWyuesmhs

[3] https://vimeo.com/731037615

[4] Rapid single flux quantum https://en.wikipedia.org/wiki/Rapid_single_flux_quantum

[5] https://phys.org/news/2008-03-future-carbon-nanotubes-superc...

If "nm" is just marketing with no relationship to any feature sizes, what is a "race" to 2mm? Isn't it just the "race" to who decides to use the moniker first?
It is somewhat proportional to transistor density.
No.

Every shrink, in theory, is supposed to mean you could have twice as many transistors per unit area. So although dimensions of transistors are similar from say 7nm to 5nm one should be able to pack twice as many in. And so when the foundry can double the transistor density, as measured over large areas, it gets to go to the next lowest number in the sequence. i.e. (7^2)/2 is roughly 5^2.

You won’t get that many, for lots of EE reasons, but in theory you could.

It’s also important to remember there are lots of things other than transistors in there. Contacts, wires, etc etc. and they have dimensions and packing requirements too. And if you can shrink or more tightly pack those things, transistor density also rises.

is Ian not writing for anandtech anymore?
No, they've been mostly power supply and cpu cooler reviews for two years now.

https://www.anandtech.com/show/17270/going-from-there-to-her...

Which is a shame. I really miss the old articles by Anand, Andrei, and Ian and their in-depth discussions about CPU and SoC architecture. I haven’t really found a consistent source to scratch that itch after they left.
Chips & Cheese has some good CPU and SoC analysis
Yup, 2nd that one as well as the link I already gave. Maybe it's the more direct replacement for old school Anand.
Thanks for the suggestions! I will check them out.
Why is he not employed at research? Semiconductor is a gigantic field growing by the year.
(comment deleted)
2nm, sure, but what about SRAM register files and caches? SRAM has pretty much stopped scaling already.

SRAM scaling is where I'd love to see some advances.

It's getting denser, but just not as fast as logic. https://www.techpowerup.com/309331/tsmc-n3-nodes-show-sram-s...

You can make them smaller (like 20%) but those SRAMs suck electrically so no product actually uses them. So in actually shipping products the SRAM is roughly the same size (like 5% smaller).

One needs to remember these things are drawn by algorithms (no one is by hand drawing billions of transistors) and there have been 20 years+ of advancements on the algorithms that draw SRAM and because of the regularity of SRAM there's more opportunity to pack.

There's just not that much fat to cut in a SRAM structure (that's purely optimizing for density) so in many ways SRAM structures are the true measure of how small things are, and they are in fact used that way. And things are really really tiny already.

We need the same 3D stacking they do on NAND flash.
You mean "2,000 picometers"

Because, I stayed in a Holiday Inn last night and now I am a Marketing professional

Slightly surprised to hear about risc v being at cutting edge nodes
Why would you be?

The RISC-V "Horse Creek" was the very first SoC Intel made on its "Intel 4" process node.