I worked at Samsung’s fab in Austin for a few years, mid-2010s. Each section of tools (photo, etch, cleans, etc.) had somewhere between 20-80 technicians sprea

I worked at Samsung’s fab in Austin for a few years, mid-2010s. Each section of tools (photo, etch, cleans, etc.) had somewhere between 20-80 technicians spread between four shifts. Mine, cleans, was I think the largest - we had about 20 techs per shift. Process, at the other end, had about 5 per shift. Each section also had N engineers, although most of them worked normal day shift hours. The fab was fully automated, in that someone would punch in an order, and many days or weeks later, wafers came out the other end. However, the machines to do all of this are incredibly touchy, prone to losing calibration, parts breaking, etc. They also require a ton of maintenance. The level of knowledge and skill to be an entry level tech is within reach for anyone who’s mechanically minded - we hired people whose only previous experience was auto mechanic. To progress to the Senior or Master tech level, though, you needed an intimate knowledge of multiple tools, to the point of having made improvements to them beyond what the manufacturer provided. I think the total number of techs in the fab was somewhere around a thousand, but I could be way off. I worked nights, so it was hard to get a sense of other shifts.