Development Of Metal Organic Chemical Vapor Deposition Equipment's Control System

Metal organic chemical vapor deposition (MOCVD) equipment is the most critical equipment for semiconductor lighting chips production. With the continuous promotion of semiconductor lighting technology, MOCVD equipment's market demand has also been greatly enhanced, but most MOCVD equipment that used in domestic factories are imported from abroad, so the development of MOCVD equipment with independent intellectual property rights not only has national level's strategy significance, but also has great market value.This thesis will focus on developing MOCVD control system, the control system consists of top level PC, programmable logic controllers (PLC), HMI and several kinds of field instrument such as flow controller, pressure controller, temperature controller, servo motor, switch and so on. The major research is summarized below: First, critical control technology for MOCVD process such as precise control of flow, pressure and temperature is studied in details. Then, the design of PLC control system especially the communication program between PLC and field instrumentation is described. Finally, the latest automation and control technology is analyzed and examined the feasibility for using in MOCVD control system.This control system has been successfully applied to RealFaith developed MOCVD equipment. The actual operation proves that this control system is powerful, simple, stable and reliable.