The Study On SOI High-Temperature Pressure Sensor

The SOI pressure sensor was developed in this paper. The full scale of the pressure sensor is between 0-1 MPa, and the temperature range is between 0-220 ℃.The structure, preparation and characteristics of SOI material were analysed simply. The stress distribution of different type pressure sensor chip in different condition were presented under the guide of finite element analysis (FEA) simulation method, especially the C type diaphragm. According to the result of simulation and characteristic of monocrystalline silicon SOI structure, a novel high temperature SOI pressure sensor with a rectangle diaphragm was designed.The SOI structure was prepared with SDB(Silicon Derectly Bonding) technique, the silicon cup was prepared with anisotropyically etching in the substrate and the resistance was prepared with plasma etching. The experiment results indicated that the test results is similar to the simulation results, it is suggested that the design of high temperature SOI pressure sensor was rational. Comparing with poly-Si pressure sensor with the same layout design and process parameters, the SOI pressure sensor had a good property of high-temperature,and the sensitivity of SOI pressure sensor was much higher.