Design Of Acceleration Sensitive Structure Of Capacitive Linkage Film

Micro-Electro-Mechanical Systems(MEMS),which combines the advantages of semiconductor technology and traditional mechanical manufacturing technology,have become the best choice to replace traditional mechanical structures due to their simple and reliable structure,high integration,easy mass production and excellent semiconductor characteristics.Capacitive silicon-based MEMS micro-accelerometer is one of the typical results of applying this technology.At present,the mainstream capacitive acceleration sensors widely use various cantilever beam structures.By controlling the displacement of the mass block to change the distance between the plates or the contact area,the capacitance changes,and the capacitance is read by an external detection circuit to realize the acceleration measurement function.However,this structure generally has a small capacitance change and a limited range,and is difficult to adapt to a large range and high impact environment.When used in weapons,blasting and other environments,the reliability is not enough,and the performance level will be significantly limited.In this paper,a capacitive acceleration sensitive structure is proposed,which greatly improves the linearity,sensitivity and anti-overload characteristics by constructing a linked thin-film variable capacitor and a sputtered metal layer instead of a mass block.The main research ideas are as follows:(1)Combined with the current research and development status at home and abroad and the specific parameter requirements for acceleration sensors in practical application scenarios,compare the advantages,disadvantages and technological feasibility of acceleration sensors with different principles and structures,and determine the contact capacitive acceleration sensitive structure as the research direction of the topic.(2)Select materials and build a structural model in COMSOL Multiphysics multiphysics simulation software according to the assumed structure principle,realize the basic function of acceleration measurement,and determine the overall design scheme.(3)The COMSOL Multiphysics software is used for further simulation analysis to study the effect of changing the material,structure and size parameters of each part of the sensitive structure on various performance parameters of the accelerometer,so as to further optimize the structure for different application scenarios.(4)Determine the specific production process and draw the relevant design layout.(5)Design an acceleration-sensitive structure case for the application field of military penetration and impact blasting,with a design range of ±200,000 g,and meet the requirements of other performance parameters of the acceleration sensor in this application scenario.