Comment by cogman10 | Hacker News Reader

Comment by cogman10 | Hacker News Reader

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> Assembling a motherboard is to semiconductor fabs as flying a toy drone is to landing a Boeing 747.

I disagree. I live next to a fab and have coworkers that have worked the fabs.

Humans in fabs are taken out of the loop as much as possible. That's because when dealing with nanoscale structures, human error is simply too common.

One of my coworkers worked at the fab during a period where they had humans running the forklift that moved the wafers from one stage to the next. That was cut out because the tiny bumps caused by a human operating the controls caused imperfections in the chips that decreased yield (the metric that matters most for a fab). They ultimately removed that work and job and replaced it with robots to carefully move the wafers.

What's complex about a fab ends up being not the frontline work, but rather the layer or 2 in the back (like designing the lithography filter for a given chip). That stuff happen outside the actual plant.

> Humans in fabs are taken out of the loop as much as possible.

This. We are talking about Atom scale here. I have as much admiration for skilled mechanics as the next guy. I heard about a lathe operator at Patek Phillip who could turn an arbor to within 1 micron precision, just by listening to the pitch the cutting tool made when trimming it down.

And when chip features were on the micron scale, humans in the loop made sense. But chip feature are ten thousand times smaller than that now--4 orders of magnitude. Anything that doesn't need a Ph.D. in solid state physics to do is going to be automated.

I'm probably revealing exactly which fab, but one issue the fab had is when it was built it was placed fairly close to the interstate. That did no matter when they were at something like 500nm. However, as they slowly pulled the node size down they started noticing random errors within their chips. It took a while to track it down but it turns out semi trucks driving past the interstate were causing defects in the chips.

They ended up installing shock absorbers everywhere to counteract this problem.

There are still, though, lots of working fabs at much larger process sizes. And some for things that won't ever modernize to a smaller one. Like parts that handle lots of power, or chips for RF purposes, etc.

I think we agree? The point is that a semiconductor fab (like a 747) is so highly automated that you don't need a bunch of low- or medium-skilled folks to drive forklifts; you need a few high-skills folks to design, monitor, debug & optimize the huge system(s).

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