How Microchips Work

[ww520]

Silicon is the perfect material for semiconductor. It has a low band gap energy between the valence band and conduction band. A small amount of energy, electricity applied to it, can knock its outermost valence electrons off and it becomes conductive. Withholding the energy, its valence electrons fall back in place and it becomes non-conductive. As if by luck, silicon is plentiful and cheap.

[XorNot]

This is missing one of the most important reasons though: Silicon Oxide.

Silicon Oxide is almost perfectly lattice matched to silicon, but completely insulating. Which means it's incredibly easy to grow features onto polished silicon wafers because the oxidation product of the material is exactly what you need in order to build up insulating features - i.e. MOSFET junctions, capacitors and conductive paths.

[bee_rider]

Clay and glass are also partially made of silicon, right?

I’ve always found of fascinating that silicon was right there at the beginning of material science, and has stuck around since. Same for copper.

I don’t actually think the universe has intentions, but copper, silicon, and dogs do sometimes make me question that belief, it is just a little suspicious that our species would have such loyal friends.

[namibj]

Low band gap is actually detrimental for transistors. The more spare band gap, the higher temperature you can operate them at.

[dogben]

And it's relatively easy to make large pure silicon single crystal.

[gshubert17]

Just before the section on Moore's Law, it says this about silicon purity:

> Electronic grade silicon (EG-Si): 99.9999999 pure ('nine nines pure') Thats one impurity atom in every 10.000.000 silicon atoms.

I believe that should be 1.000.000.000 (10^9 atoms) to correspond to nine nines pure. Just as one impurity atom in every 100 (10^2) atoms would be 99% (two nines) pure.

[ExAr]

Hi everyone! I am the author of the website exclusivearchitecture.com.

Thanks everyone for all the positive feedback - so rewarding to see! I have already made some corrections to a detail where I gave an incorrect number with the "nine-nines-purity" and it should be 1 impurity in 1.000.000.000 silicon atoms. Thanks gshubert17 for pointing that out.

I have noticed that my website is currently down with a timeout - sorry for that. I hope this is going to be resolved asap.

Cheers! MK

[ninju]

> I have noticed that my website is currently down with a timeout - sorry for that. I hope this is going to be resolved asap.

HN hug of death strikes again

[gdevic]

I loved the article! Spot on and just the right depth for the article size (I am a CPU architect).

[0wis]

I am not an expert but it seems like a great source to understand chips without getting top deep. It reminds me the classic « Nand 2 Tetris » course [1] with less involvement indeed. Thanks for the developer and thanks for sharing. Curious to know industry expert comments !

[1]:https://www.nand2tetris.org/

[nairboon]

There is also the NandGame: https://nandgame.com/

[xg15]

From the "Overview" page:

> Microchips – also referred to as integrated circuits – are considered to be among the greatest technological achievements of the last century. Their invention has paved the way for a digital revolution that keeps changing the world to the present day.

...

> The ENIAC computer from 1946 had over 17.000 vacuum tubes and suffered a tube failure on average every two days, which was time-consuming to troubleshoot and repair. With the invention of the transistor in 1947 by Bell Labs, the components became significantly smaller, but the transistors were still wired together individually. This reduced power consumption of those computers and their overall size, but not their wiring complexity. It was not before the invention of integrated circuits before computers became way more efficient and easier to operate and maintain.

I find it on some level hilarious that one of the fundamental breakthroughs that allowed the technological revolution pick up speed and perception-wise cross the barrier from "sophisticated machinery" to "magic" was, in some sense, proper cable management.

[jpm_sd]

It's really /elimination/ of cable management. Essentially the same thing that makes printed circuit boards superior to wire wrapping. Turned a manual labor process into a (photo)lithographic process. Not that different from the replacement of hand-lettered manuscripts with the output of a printing press!

In larger electronic and electromechanical systems, cables and connectors ("harnessing", collectively) are still major weak points.

[agumonkey]

I guess with scale, the tiniests of details become the bottleneck :)

[kken]

I am really impressed by the clarity of the illustrations in the article.

[gslin]

https://archive.is/hYvUp for most contents.

[imperialdrive]

I wonder where we would be if a printed copy of that post was delivered back to TI and Intel etc R&D labs 50 years ago.

[lencastre]

Interesting, Turing Complete is also from NAND to microcomputer.

[1] - https://store.steampowered.com/app/1444480/Turing_Complete/