Most companies only make a small fraction of the tools you need for a full fab; for examples of heavy hitters in key areas like lithography, chemical mechanical

Most companies only make a small fraction of the tools you need for a full fab; for examples of heavy hitters in key areas like lithography, chemical mechanical polishing, and ion implant, see ASML, Nikon, Canon, Applied Materials. For any given tool, there are usually 1 to 3 major vendors.