I want to show you an abandoned integrated chip factory. Crystals for chips KR1821RU55B, M1821VI85A, M1821VI54, 1564IE19, etc. were manufactured here.
The last year of production is 1993, after which the factory closed and remained abandoned for more than 25 years.
On the photo below you can see round plates with a matrix of chips.
Integrated circuits have dozens of layers, and each of them requires its own mask. In the photo, you can see the masks for different chips.
The production of chips consists in the imposition of thin layers with a complex “pattern” on silicon substrates.
Trays with substrates are loaded into a quartz tube, the working area of which is placed inside a high-temperature furnace. The tube is fed diffusant carried by a carrier gas (argon or nitrogen) and an oxygen stream. The photo shows an automated diffusion system model ADS-6-100.
You need to project images from photomasks onto plates, multiply the reduced image of the topology onto workpiece, etc. The photographs show a part of such equipment, as well as a pair of laser ellipsometers to control parameters.
A significant number of machines (welding, packaging) over a quarter of a century were destroyed by employees in search of precious metals.
Source: Ralph Mirebs