Development Of An Automatic Process Control Application Software For The Electrodes Preparation Of Quartz Crystal Resonator By Pulse Magnetron Sputtering

the key technology of quartz crystal resonator is the electrodes preparation accurately.the application of magnetron sputtering technology in "Electrodes Preparation" is a good wayto solve the “poor adhesion” problem compare with the evaporation of silver. This thesis maindevelop a application software of automatic process control in the twin target pulse magnetronsputtering coating system for electrodes preparation with double-sided so as to meet theindustrial production needs of the quartz crystal resonator electrodes preparation. thedevelopment strategy of corresponding process control system is always running through theprinciple of security, convenient and utility. the PC user interface was development usingVC++6.0for development tool, the control program of sputtering coating process weredesigned based on Siemens S7-200PLC for the lower machine. Therefore, the developmentsoftware of automatic process control for twin target pulse magnetron sputtering coatingsystem was implemented.Through the control requirement analysis of the sputtering coating process flow after theintroduction of the quartz crystal resonator electrode preparation technology, the top-downarchitecture of the development process control software was determined. Follow theRS-232-C interface rule, API serial function was used to open and close the serial port. TheSiemens S7-200free port protocol was used to accomplish the communication between theupper computer and the lower PLC.The user information of Ethernet address and hard disk serial number detected willbe verify with the only authorization code packaging in system login procedures so as tojudge the legitimacy of the users than to protect the intellectual property rights effectively.The PC user interface developed in this thesis mainly realizes the5function module suchas the operation mode control, process parameters setting, the process parameters real-timedisplay, manual process control and the condition monitoring. The setting of processparameters in accordance with the "Frequency point Setting used Commonly" with pull-downmenu and "Frequency point process parameters Setting by User" for different products.In order to meet the control needs of different electrode film thickness, the sputteringpower and the number of cycle period was used in PLC program design technique. As for asmall film thickness different control, the increase or decrease of the sputtering power wasused for fine control. According to the requirement of process parameters, such as parameterinitialization, automatic vacuum supply, ionization cleaning, chromium film sputtering andsilver film sputtering process control program were developed. The digitalapproximation control strategy was used to prevent the analog output overshoot of sputtering power.According to the process running state logic judgment，the main program of process controlsystem supervise the activation and termination of the subroutine, so that the automaticjudgment and efficient operation of the quartz crystal resonator electrodes preparation processwith double-sided has been realized.The development of process control with twin target pulse magnetron sputtering coatingsystem in this thesis have provided with the characteristic such as simple, practical, and lowcost. The operation result of model machine with this automatic process control software hasrevealed that it is an excellent control system with high process stability experimentally.