Porous Silicon Humidity Sensor Production Performance Studies

The humidity sensors are studied widely with the importance of the humidity in our daily life.Lately,Moisture information more and more people's attention. High accuracy, high sensitivity, temperature coefficient, good stability, long life, fast response, anti-corrosion, manufacturing process is simple, easy-to-volume, low cost humidity sensor performance is ideal for the basic requirements, and appropriate in the wide temperature range, humidity range.As humidity device applications is different,the requirement for the technology of the humidity sensor will be different according to the applied field.On the manufacture eye,there will be great difference in performance if we take the different material,structure or technology.The article has studied two materials of porous Silicon,analysised the mechanism of the capacitive humidity.First, porous silicon was prepared by electrochemical etching as a well as porous silicon structure is studied.Then,capacitive humidity sensor was made with porous silicon as a medium. The performance of the humidity sensor to test, and ultimately obtained (80mA/cm2, 30min) and (40mA/cm2,20min) conditions (the conditions for the corrosion of porous silicon growth conditions),The sensor's characteristics were tested under different humidity value,which will help to further research in future.Completed the humidity signal acquisition circuit and display circuit design, will produce the capacitive humidity sensor capacitance, through the microcontroller is programmed into a specific relative humidity value, the circuit through the LED digital display shows relative humidity values.