Research And Development Of Productive MOCVD Electric Control System

Metal Organic Chemical Vapor Deposition is a technology of producing compound semiconductor by depositing thin layers of crystal over the surface of the substrate,mainly used to manufacture light-emitting diodes.The MOCVD device is the key equipment for photonics industry.National engineering technology research center for led on Si-Substerate Nanchang University R&D staff,after more than a year of hard work,finally succeeded in the development and put into operation of37×2"GaN based MOCVD devices.At the meantime,to meet the requirement of market and seamless epitaxial production,MOCVD technology requires constant improvement and optimization of electric control equipments.The main task of this paper is to develop electrical control system for new models of61×2" GaN based MOCVD.The schematic design of MOCVD is mainly completed with electric control system based on industrial ethernet and fieldbus network comprising;electrical and control system hardware circuit design;main circuit and power circuit design of the heater system,control system of the main circuit and control circuit design,safety interlock circuit design;DeviceNet network circuit design and software configuration,programming,major circuit design including the media selection of the nerwork,the network structure is composed of the power supply selection and allocation on the network;PLC program design of the manipulated operation of the reaction chamber and automatic nozzle brush.The new type of MOCVD equipment,through unit testing and debugging and running in good condition,can fully meet the requirements of production.61×2"control system compared with the37×2",performance is more stable,the control is more safe and reliable,higher degree of automation,lower production costs.Development of new type equipment lays a solid foundation for further industrialization of domestic MOCVD equipment.