Research On Structural Design And Packaging Technology Of Graphene MEMS Aviation Air Pressure Sensor

Airborne atmospheric data measurement system is an important airborne equipment to ensure the flight safety of aircraft.One of the core parameters of measurement is air pressure.The key of air pressure measurement is the pressure sensor technology that a cts on the front end of the measurement system.With the emergence of demands for miniaturization and unmanned aircraft,the development of MEMS technology and the discovery of the large elastic deformation characteristics of graphene materials,the design of graphene MEMS pressure sensors with small size,light weight and low power consumption has become a new research direction in the field of sensors.Due to the particularity of MEMS packaging,exploring the packaging method in the sensor design stage,d esigning the packaging system according to the principle of the sensor and studying the effective packaging process can reduce the cost of research and development,shorten the development time of the product,and improve the technical performance of the p roduct to a certain extent.Aiming at the problems of miniaturization,high environmental adaptability and high precision small range air pressure sensor needed by aeronautical atmospheric data measurement system,this paper selected twodimensional nano-material graphene instead of silicon-based material,proposed to design sensor structure using two reading modes of fiber interference and tunneling current,and applie d COMSOL software to simulate it,and studied the packaging method of sensor.This paper can be divided into three p arts:The first part mainly complete d the structure design and analysis of graphene fiber Fabry-Perot cavity type MEMS pressure sensor.Graphene film was used as the reflection diaphragm and pressure diaphragm to design the structure of pressure sensor.By modeling and simulation with COMSOL software,the relationship between the center displacement of graphene film and its pressure,effective radius and t hickness was investigated in turn.The calculation formulas of the parameters such as the pressure of the sensor and the displacement of the center of the graphene film were summarized.The second part mainly complete d the structural design and analysis o f graphene tunneling current MEMS pressure sensor.Graphene film was proposed as a pressure-bearing diaphragm and a design sensor structure for the diaphragm with quantum tunneling.By modeling and simulating COMSOL software,the relationship between the c entral displacement of graphene film and its ambient pressure and external control voltage was investigated.This paper summarized the calculation formula of the displacement of the center point of the graphene film when the two variables act simultaneousl y.Therefore,when the displacement of the center point of the graphene film was calculated using the optical fiber interference principle,the air pressure of the environment where the sensor was located can be obtained.The third part mainly complete d the packaging process of graphene MEMS pressure sensor.According to the structure of two kinds of graphene MEMS pressure sensors in this paper,the micro-scale package with adhesive was proposed.Combined with the characteristics of dispensing technology,time pressure needle dispensing was selected,a dispensing system was designed,and adhesives and dispensing equipment were selected to verify the feasibility of the packaging method and conduct p ackaging experiments.