Abstract:Epitaxy process is a frontend process of IC manufacturing lines, it provides the perfect single crystal epitaxial layer substrate for the followup process. The tool executing epitaxy process for silicon wafer is silicon epitaxy equipment, its control system software is a distributed software which is based on PLC and host computer. Therefore, driver software for communication between PLC and host computer has very important meaning to realize the whole control system. A scalability, low coupling, reusable PLC driver software was designed for the equipments control system based on FINS protocol, in which object oriented and component oriented thinking and modular organization management mode were used.