Design And Research Of Embedded Anodic Bonding Monitoring And Control System

Anodic bonding is one of the key packaging technologies of MEMS,which is widely used in the preparation of MEMS device.At the same time,anodic bonding equipment is the basis for implementation of the anodic bonding technology.However,existing anodic bonding equipment has the problems of device separation,large size,and high cost.To solve the problems,this subject designed and implemented a set of embedded anodic bonding monitoring and control system,which can realize real-time monitoring and control of the entire anodic bonding process,ensuring the miniaturization,low cost and high performance of the system.This subject designed a control motherboard that integrates fuctions of voltage control,temperature measurement and control,and current acquisition.The motherboard uses the STM32F103RET6 chip as a processor,controlls the output voltage of the high-voltage DC power from 0 to 2000 V by the adjusting voltage of AD5612 from 0 to 5V,controls the conduction time of the heating resistance wire by the triac circuit and collects the temperature by K-type thermocouple,detects and amplifies the current signal of microampere level by INA180 circuit and uses AD7980 for A/D conversion,communicates with the host computer by the Ethernet module.This subject designed STM32 software and host computer software.Based on STM32F103RET6 chip,this subject transplanted u COSii operating system and Lw IP protocol stack,and designed multi-task program according to the system functions.The host computer software is designed through Lab VIEW tool,which can monitor and control the voltage,temperature and current during the entire bonding process,and provide functions such as data curve display and data saving.In addition,due to the problems of the heater such as large thermal inertia and serious lag,the PID algorithm is used for temperature control and simulation is performed on the feasibility of PID.Finally,this subject carried out linkage debugging of the system.Through the voltage test results,the linear deviation of the high-voltage DC power itself was corrected,so that the output error of the high-voltage DC power was within ±2V.The current test results showed that the effective number of bits of AD7980 was 13.99 and the error of weak current acquisition was within ±10?A.The PID parameters were adjusted through the engineering tests to ensure that the temperature was controlled within ±1? of the set value.At the same time,this system was used to complete silicon-glass anodic bonding.The test results show that the system can complete anodic bonding experiment reliably and stably,and can meet the design requirements.