Research Of Porous Silicon Relative Humidity Sensor

As a important sensor, humidity sensor plays a pivotal role in human life. Since the advent of the humidity sensor, it has about two hundred years of history.the development pace of development of humidity sensor is so amazing in these two countries.Now humidity has been developed in the direction of miniaturization, intelligence, integration and so on.This paper analyses and compares the sensitivity of two types of porous silicon humidity sensor-the sandwich type and the tiled type. A structure of porous silicon humidity sensor which combines the advantages of these two kinds of structure is designed in this paper.Finally the paper shows the production process for the sensor.The results are as follows:1.Exploring a new methods and apparatus for producing a porous silicon material on the basis of the conventional dual-slot,it designs a new apparatus.The apparatus can be adapted to the preparation of large-area and the particular location of the porous silicon.2.The thesis compares the advantages and disadvantages of the two structures of traditional capacitive humidity sensor.And on this basis,it design a new structure.And it demonstrate the advantages of this structure from the theoretical and experimental.The structure used as a heating circuit for polycrystalline silicon sensors dehumidification, ensure the self-absorption of humidity sensor. Electrode layer is deposited on top of the passivation layer Si3N4, can effectively prevent the degradation of the electrical properties and prevent moisture leakage current path causes of ions or other external contaminants caused by the impact of the next measurement.3.Showing the construction process for the preparation of the humidity sensor,and using technology for through-silicon vias filled with metal electrodes.