IBM/Intel/Samsung buy tools from various companies. By "tools", I really mean huge pieces of instrumentation that cost many (tens to hundreds) millions of dollars from other companies that are used for the various processing steps (deposition/growth of materials on wafers, patterning resists, etching, etc). The development of each of these tools is immensely difficult and challenging and making them talk to each other and designing manufacturing pipelines is another immense challenge. IBM/Intel/Samsung's job is to design chips (a immense challenge on its own), come up with a process to manufacture them, and then take each of these very complex tools, integrate them into a manufacturing pipeline (with QC), and manufacture the devices that they want.