Mathematical Compact Models of Advanced Transistors [pdf]
www2.eecs.berkeley.edu
www2.eecs.berkeley.edu
https://ieeexplore.ieee.org/abstract/document/9796144
> These are physics/EE PhDs.
> They are not experts in nonlinear optimization.
No one that is an expert in nonlinear optimization has a PhD in... nonlinear optimizations. Typically their degree is going to be in Mathematics, Computer Science, Electrical Engineering, or Physics. The last 2 are commonly found in any strongly mathematical subfield.
This is kinda like saying a physicist can't program or is terrible. Maybe they can, maybe they can't. My senior undergrad CS students are worse programmers than most graduate physicists I've seen. One of the best programmers I know has a PhD in Mechanical Engineering and works at a national lab. I asked him how it ended up like that and he said to get his PhD work done he had to do a lot of low level stuff, related to what we were doing.
I do agree with your point fwiw, I just thought if we're going to nitpick we should nitpick ;)
Lol wut. On the contrary there are absolutely zero people with a "PhD in Mathematics" and definitely very many people with PhDs whose dissertations have the words "nonlinear optimization" in them.
> there are absolutely zero people with a "PhD in Mathematics"
On the contrary, there is absolutely zero departments of nonlinear optimization. This is actually a true fact and not an alternative one.
> whose dissertations have the words "nonlinear optimization" in them.
You seem to be missing critical context, which is what I was responding to
>> These are physics/EE PhDs. They are not experts in nonlinear optimization.
[0] https://mathematics.stanford.edu/academics/graduate-students...
Are you a bot? The text is very clear - I said `PhD` not `degree`. You cannot get a `PhD in Mathematics` - the title of the PhD is never ever (ever) `PhD in Mathematics` (or `Physics` or `Electrical Engineering` or `Computer Science`). In fact it's literally only ever `Doctor of Philosophy` that gets listed on the award. The department is also listed on the award as `awarded by X department` but it matters about as much as the football team of the school. The only thing that matters is the title of the dissertation. That's how you get people in physics departments doing dissertations that are pure math and vice-versa.
If you still don't understand what I'm saying I'd be happy to take a pic of my PhD certificate and send it to you.
>On the contrary, there is absolutely zero departments of nonlinear optimization. This is actually a true fact and not an alternative one.
Lololol:
http://math.ac.vn/en/cao-hoc/211-organization/departments/de...
and if you actually read that page, you'll see it reveals that usually these departments are called "Department of Operations Research", such as
https://www.orie.cornell.edu/orie
> You seem to be missing critical context, which is what I was responding to
You seem to have selective reading/recall abilities - I have directly quoted already what I'm responding to
> No one that is an expert in nonlinear optimization has a PhD in... nonlinear optimizations
So I'll repeat - there are many many people that literally have PhDs in nonlinear optimization.
> http://math.ac.vn/en/cao-hoc/211-organization/departments/department-of-optimization-and-control-theory/337-thong-tin-chung.html
Maybe there are actually universities with departments in optimization. But if so, they are exceedingly rare. Departments are generally not very specialized. But hey, some universities do weird things.
> You cannot get a `PhD in Mathematics` - the title of the PhD is never ever (ever) `PhD in Mathematics` (or `Physics` or `Electrical Engineering` or `Computer Science`).
THE DEGREE OF DOCTOR OF PHILOSOPHY IN PHYSICS
As for me, you'll have a terrible time trying to convince me that the words I read on my diploma are not real.
[0] http://math.ac.vn/conference/SWSAAG2024/index.php?option=com...
Are you asking about EUV lithography? That's a manufacturing technique, but this thesis is about modeling the physics of how a transistor operates, not the process of building the transistor.
Classic hn well akshully.
I think the crux of the matter is the transition from 7 nm down to our modern nodes, where the major change was not only going from DUV to EUV, but perhaps more importantly the change from finFET to multi-gate or gate-all-around FET (GAAFET), where this model probably needs significant updates to be still valid.
This feels like a hn breakthrough.
This is if you run full electrical circuit simulation. For complex digital chips you can't do that due to insane compute requirements. There comes in modeling and yield estimation wizardry in. But if you want to simulate the hell out of a reasonably small circuit (< 100M nodes), you can do that extremely accurately.
While the models used in commercial EDA tools are based on those published by academic research, they may have various secret tweaks.
What belongs to the foundries, e.g. TSMC, Samsung, Intel, UMC, Global Foundries etc., or to the in-house semiconductor plants of certain companies, are the values of the model parameters, which are determined by fabricating and measuring a lot of test devices.
The foundries provide the model parameters to their customers included in the so-called Process Design Kits. For each semiconductor device fabrication process there is a PDK.
In order to design some custom integrated circuit, you need to obtain the PDK and install it in your simulation tools.
Unfortunately, the foundries with up-to-date fabrication processes keep secret their PDKs. Otherwise many people could attempt to design something like a CPU competitive with Intel, because unlike for fabrication, for design all you need is a computer and time.
Attempting to design a CPU using one of the obsolete PDKs that are available publicly, which are at the level used for CPUs like Pentium 4, more than 20 years ago, is futile, because the optimal design choices are very different for such ancient CMOS fabrication processes, in comparison with modern processes, so you would not learn more from that experience than when targeting an FPGA.
TSMC has their own C-library on top of BSIM models for FinFETs because BSIM isn't covering what they need. I don't know what will they use for GAA stuff.
- "Researchers get spiking neural behavior out of a pair of [CMOS] transistors" (2025) https://news.ycombinator.com/item?id=43503644
- Memristors
- Graphene-based transistors
EUV and nanolithography?
SOTA alternatives to EUV for nanolithography include NIL nanoimprint lithography (at 10-14nm at present fwiu), nanoassembly methods like atomic/molecular deposition and optical tweezers, and a new DUV solid-state laser light source at 193nm.
Getting an accurate idea of how things really work down at that level is very refreshing.
Also, it scratches an itch I've had for a long time, namely to understand how much quantum mechanics is really needed to accurately predict/model modern FETs.
https://www.amazon.de/-/en/Operation-Modeling-Mos-Transistor...