基于模糊控制的HVPE生长设备温度控制系统

氢化物气相外延（hydride vapor phase epitaxy，HVPE）工艺的关键是确保加热炉的温场恒定和高精度控制。由于HVPE生长设备温度控制过程涉及多个加热温区，以及温度测量元件和电阻加热炉温度传导引起的延迟，其温度控制存在超调过大、控制精度低和调节时间过长等问题。为实现HVPE生长设备反应室内温度的精准调控，将模糊逻辑应用到PID （proportion integration differentiation，比例积分微分）控制中，设计系统各温区的模糊自适应整定PID控制器。依据实际设备与相应技术要求，设计研发了一套基于PLC （programmable logic controller，可编程逻辑控制器）、温度控制电路以及模糊自适应整定PID控制的HVPE生长设备温度控制系统。Simulink仿真结果与实测结果表明，模糊自适应整定PID控制器可以应用于HVPE生长设备的温度控制系统，且控制效果较好。研究表明，所设计的温度控制算法与温度控制系统能够很好地满足GaN材料生长的工艺要求，具有一定的实用价值。

Temperature control system of HVPE growth equipment based on fuzzy control

The key to hydride vapor phase epitaxy (HVPE) process is to ensure constant temperature field and high accurate control of the heating furnace. However, there are some problems such as large overshoot, low temperature control accuracy and long adjustment time in the temperature control process because the temperature control process of HVPE growth equipment involves multiple heating temperature zones, coupled with the delay caused by temperature measurement elements and the temperature conduction of heating resistance furnace. In order to achieve the precise control of the temperature in the reaction chamber of HVPE growth equipment, fuzzy logic was applied to the PID (proportion integration differentiation) control, and the fuzzy self-adaptive tuning PID controller in each temperature zone of the system was proposed. According to the actual equipment and corresponding technical requirements, a temperature control system of HVPE growth equipment was developed based on PLC (programmable logic controller), temperature control circuit and fuzzy self-adaptive tuning PID controller. The Simulink simulation results and measured results showed that the fuzzy self-adaptive tuning PID control could be applied to the temperature control system of HVPE growth equipment, and the control effect was better. The research indicates that the designed temperature control algorithm and temperature control system can well meet the technological requirements of GaN material growth, which has certain practical value.