Pretty mind blowing, this is a great article that brought together a lot of the things I "kinda" knew about IC's. I try to imagine the complex machinery required to manufacture these things. Some things would just be impossible to make after the zombie apocalypse. Something on a lot of peoples minds in these times.
How hard would it be to make a simple transistor with basic materials. To produce doped silicon out of sand, to affix a wire lead under a microscope. I often think back to a picture of the first Bell Labs transistor under a glass jar I saw once. I think someone posted a video about a home brewed vacuum tube a long time ago, but a home brewed 2N2222 would be a much greater challenge.