To expand a little on this: a chip fabrication process is a series of steps from incoming bare wafers to finished chips (potentially multiple wafers get combined into a finished chip, as well). To build up the physical structure of the chip, there are a series of steps where different materials are deposited or grown on the surface, masked through photolithography, and removed in order to shape the structure of the chip layer by layer. Each of these depends on not just what that layer itself requires (material, thickness, resolution), but also on the layers around it, because these steps are not independent: a lot of process design is in finding a way to construct a given chip that means each step is compatible with the others.
What's more, the configuration and flow of the machines used for each step are quite sensitive: you cannot in general just stand up another fab with the same machines, apply the same settings, and hit go on a new chip design and expect any yield: you need to dial in each step, certainly for each process, and likely for each design. This makes switching things around more difficult as well.
So, while in general a fab will have certain common features: spin coaters, photolithography machines, vapor deposition chambers, ovens, etc, the number and specification of each one will vary based on the process, and a production fab will generally not want to change their process drastically, or even to swap between different designs too often.