基于LabVIEW的碳基薄膜制备自动控制系统开发研究

Development of LabVIEW-based automatic control system for tetrahedral amorphous carbon film preparation

基于Lab VIEW图形化编程软件和PCI1711多功能卡,设计开发了用于真空等离子镀膜机的自动控制系统,实现了对四面体非晶碳薄膜制备工艺的自动控制。该系统共分为5个模块:镀膜机各设备的电源控制(70路)、模/数转换(32路)、数模转换(32路)、PWM输出(6路)、机间通信(采用RS 485总线)。对电源的控制通过电磁继电器实现;数/模转换通过开关量输出接口控制D/A转换器予以实现;模数转换通过多路模拟开关芯片进行选通后送到数据采集卡的模拟量输入端予以实现;通过RS 485总线实现对复合真空计、涡轮分子泵、气体质量流量计等的控制与数据获取。实验表明,该控制系统具有对真空度、离子束表面改性、真空磁过滤多弧镀膜的实时监测与控制功能,实现了薄膜制备的计算机控制。

A automatic control system for vacuum plasma coating machine was designed by means of graphical program-ming software LabVIEW and data acquisition card PCI1711,which realized automatic control of tetrahedral amorphous carbon film preparation. The design of the system hardware and the core software is described in detail. This system can be divided in-to five modules：power control,A/D conversion,D/A conversion,PWM output and inter-host communication. The power sup-ply is mainly controlled by electromagnetic relay. D/A conversion is implemented by output on-off interface. A/D Conversion can be achieved by the multi-channel analog switch chip and data acquisition card. The composite vacuometer,molecular pump and gas mass flowmeter ,and their data acquisition are controlled through RS485 data bus. The experiment results indi-cate that the control system has the real-time monitoring and control functions of vacuum degree,ion beam surface modifica-tion,and filtered cathode vacuum arc coating. Computer control of film preparation was realized.