You need QM to even explain why electrons don't fall into the nucleus. So I'd say if you want to understand anything then you need QM.

There's this quote which I think applies here: if you want to bake an apple pie from scratch, you first need to invent the universe.

True, but transistors do not behave in a newtonian physics manner, whereas we do just fine understanding most physics using conventional newtonian mechanics.

This makes me wonder what Newtonian physics we actually use in computing?

Non-transistor electronics relies on Maxwell's Equations. While not Newtonian mechanics, it is part of classical (pre-Einstein) physics.

QM would be ultimate foundational understanding. A transistor is a valve. Here, problem solved :D

A generic course in QM won't really help you understand electronics any better. Perhaps if you have a background in electronics or if the course makes attempts to link QM with electronics but otherwise it's just relatively abstract physics.

I don't know any program of study that would get sufficiently deep enough to get to semi-conductor quantum tunneling (year 2/3 class) without having some foundational E&M to motivate the QM to begin with (pure math here being a more exceptional but rare case). I think the beauty of QM at that point is that it looks and feels a lot like differential field work of EM and Lagrangian mechanics but maps to quantized numerical spaces, where jumps and little shoots like that happen all the time (spontaneous crystal domain alignment in magnets for example). If you were able to get sufficiently skilled in intro QM, it would absolutely help study in E&M.

If you E&M questions are just node solving, linear algebra and difeq is all you need for E&M to solve "most" work. You do a lot of specialized versions of that in QM and as mentioned above the people doing the actual semiconductor design are so highly specialized that they are often not transferable to other problem domains and require fundamentally different approaches. Not sure any non-PHD study will really help one advance the field in a meaningful way. Study of QM i would say sufficiently enriches all physics verticals that if you are capable, it's worthy of individual pursuit, but also makes total sense to study as part of a curriculum taking place after intro E&M.

Quantum Tunneling in everyday life: https://www.discovermagazine.com/the-sciences/how-quantum-me...

Now that you mention it. After the QM course there was a solid state physics course where quantum effects show up and where it's applied to electronics/semiconductors.

> A generic course in QM won't really help you understand electronics any better.

Caltech had an elective course for freshman about how semiconductors worked up through flip-flops and registers. I took it. It involved QM and yes, tunnelling. So it's doable for mortals.

Very interesting discussion thread re how much knowledge you need or can aquire on complex technology platforms. The goal is key here, I presume.

I read Charles Perzhold's Code, worked through parts of SICP, developed a bit of high level code software, have a very good knowledge of chemistry, lithographic processes (and QM, half forgotten by now). And yet it is not enough to get a good understanding of the modern computer - EE, compilers, OS de, networks, ... wiring the while thing together, et cetera.

I see the point in historical approaches, but it is quite time consuming. At the end, you will most likely attack problems at one to three levels in the "stack".

What would you consider to be an above average conceptual tool and skill set for the modern hacker?

Yes, I can see how it would help there. I was more thinking of the situation where you take a QM course and don't apply it to an electronics problem. I agree that it's doable for mere mortals, but it might take a fair bit of time!

Do FETs really require QM to understand them?

The handwavy explanations you'll find in electronics textbooks are sufficient to enable you to effectively design electronic circuits around them. But personally, I found those explanations inadequate.