Research On Nano-Zinc Oxide Four Array Silicon-based Integrated Gas Sensor

China's industry is developing rapidly,and the production of toxic and harmful gases seriously affects people's health and property safety.With the increase of people's requirements for the detection of toxic and harmful gases,MEMS technology has become the focus of research in modern sensors.The micro-structured gas sensor is the core of toxic and harmful gas detection technology.This type of sensor has the advantages of small size,low power consumption,integration,and intelligence.Compared with traditional gas sensors,it can better endanger gas safety Detection.This thesis combines the synthesis of gas-sensitive materials and the design of a detection system to produce a nanozinc oxide four-array silicon-based integrated gas sensor.This project designed a nano-zinc oxide four-array silicon-based integrated gas sensor with nano-zinc oxide as a sensitive material,silicon as the substrate,and Pt resistance wire as the signal electrode.Ethanol is the detection object,and the gas-sensitive characteristics of the sensor are detected.The main research contents are as follows:A MEMS sensor structure is designed.At the same time,the sensor microstructure is thermally analyzed by ANSYS finite element analysis,the sensor structure is designed,and the thermal stress under the working state of the sensor is simulated and theoretically analyzed to verify the feasibility of the sensor structure..The process of preparing nano-zinc oxide gas-sensitive materials by sol-gel method is introduced in detail,and noble metals such as Pt,Sb,Nb are doped according to a certain ratio to improve the gas-sensitive characteristics of gassensitive materials.Differential thermal weight loss analysis and testing,and completed the coating,sintering,and soldering of sensitive materials,etc.,to make the finished sensor unit.A silicon-based MEMS microstructure sensor arraywas prepared,and each unit sensor of the four-array was coated with a sensitive material with a different doping ratio.This article integrates four different sensing units on an electronic circuit.Perform performance simulation tests on MSME microstructures,including thermal analysis and thermal stress,build a hardware platform to detect and analyze the sensor's characteristic indicators such as concentration characteristics,sensitivity,response-recovery characteristics,repeatability,consistency,etc.The test gases in this article include formaldehyde,ethanol,and ammonia.Performance tests were performed on the four-array silicon-based integrated gas sensor,including sensitivity,concentration characteristics,temperature characteristics,response-recovery characteristics,and selectivity to different gases.The test results show that the sensor designed in this paper is better for formaldehyde and ethanol and less sensitive to ammonia;the optimal working voltage is 5.5V,and the response time and recovery time are 15 s and 25 s.