Research Of Vacuum Microelectronic Acceleration Sensor

The acceleration sensor is the key basic component for IMU (Inertial Measurement Unit) to sense and analysis the motion information. With the development of IMU, there is a growing demand for acceleration sensor with excellent temperature stability, resistant to radiation, quick response, low power and small size. As a result of development, many types of acceleration sensors appeared, such as piezoresistive type, capacitive type, piezoelectric type and tunnel type, etc. Vacuum microelectronics is an emerging and evolving technology. The vacuum microelectronic devices, appeared in the early 90s, arouse the attention all over the world for the advantages of excellent temperature stability, low power consumption, resistant to radiation, quick response. Characterized by field emission in vacuum micro chambers, it has found applications in the display field, and more recently in sensor technology. Based on the basic principles of vacuum microelectronics, a new kind of integrated vacuum microelectronic acceleration sensor is presented. The acceleration sensor has been developed using MEMS technique, microelectronic technique, and vacuum electronic technique. It can be widely used in navigation and aerospace, industry automation and car airbag control and so on. The research of such kind of acceleration sensor is of great scientific significance.In this paper we seek to report on a novel method of utilizing field emission in acceleration sensor. Emission currents are directly related to, among other parameters, the distance separating the emission cathode and anode. When either or both electrodes are micromachined in a cantilever beam capable of deflection under the influence of an external force, the emission current detected will be a direct measure of force magnitude. In order to calculate the deflection parameters of cantilever beam, a full static, mode and harmonic finite element analysis (FEA) using the ANSYS Finite-Element program is performed. The results derived from FEA are well analyzed for the discipline of structure and its displacement, resonant frequency and mode. On the base of these analyses, optimization design and arts design are performed and the layouts of masks are plotted. The theory model of this kind of acceleration sensor is founded to guide the fabrication.