| Silicon micromechanical accelerometer is one of the research hotspots of MEMS, it has advantage of small size, low cost and easy to be batch produced. Silicon resonant micro-mechanical acceleration sensor is a kind of high precision sensor, it outputs frequency signal, so it is difficult to be interfered by the environment. Compared with other types of MEMS acceleration sensor, Resonant acceleration sensor ‘s output signal can be processed without A/D conversion, so the detection will be easier. From the above, exploring and researching the Silicon resonant micro-mechanical acceleration sensor is of great significance. This paper designed a new type of of Silicon resonant micro-mechanical acceleration sensor using the working mode ofelectro-thermal excitation and piezoresistive detection. Compared with the previously reported Z axis resonant acceleration sensor in the literature, the Silicon resonant micro-mechanical acceleration sensor designed by this paper simplified device structure and decreased Encapsulation difficulty, And can effectively eliminate the Cross shaft coupling interference caused by In-plane acceleration.Around the device’s design and production, this paper analyzes, this paper analyzes the mechanical structure of the silicon resonant micro-mechanical acceleration sensor, obtains the best condition of eliminating the cross coupling interference caused by in-plane acceleration. Calculate the structure parameters of the device, designing the complete process. multi-layer beam structureVerifing the critical process in the manufacturing operation of the device one by one. Mainly studied the preparation of silicon dioxide /silicon film, measurement of residual stress, stress compensation of the resonance beam; in order to achieve the mechanical structure designed by this paper, using the method of mask-maskless etching to etch multi-layer beam structure. And according to different corrosion solutions and their additives we have done a lot of experiments, analyzing the corrosion characteristics of maskless etching using different corrosion solutions and their additives, calculating the value of r3, finding the iodine-supersaturated KOH etchant having the best corrosion characteristics and the minimum r3;for the convex corner protection in process of etching, one mask pattern was put forwards, and proves feasible by a lot of experiments; analyzing and introducing different resistors and wires. |
