Optical Fiber Temperature Sensor Based On Temperature-Dependent Optical Properties Of ZNO Film On The Sapphire Fiber-Ending

This thesis introduces a new type of optical fiber temperature sensing system, based on the ZnO thin film's negative temperature effect of the optical absorption edge.Zinc oxide is a versatile semiconductor material with a wide band-gap of 3.37eV at room temperature (RT).It is the Novel Semiconductor thermo-sensitive material. ZnO thin film was first grown on the sapphire fiber-ending by electron-beam evaporation (EBV),and was made as a temperature probe. AFM and XRD showed:it has smooth surface and also strong crystallization quality and strong (0002) orientation.Two kinds of the design were proposed, the experimental results were made a detailed analysis to prove the feasibility of the program. The transmittance spectra showed that the sharply optical absorption edge red shift with increasing temperature, and the obtained temperature-dependent band gap energy for ZnO corresponds to the linear formulation of Eg(T)=3.4075-5.0100×10-4×T. As the temperature sensor is to use c-axis oriented sapphire fiber (melting point of 2072 degrees Celsius) and the ZnO film (melting point of 1975 degrees Celsius) by the composition and the other traditional fiber-optic temperature sensor temperature range has been greatly improved compared to the future by improving experiment heating device, measuring range can be further expanded. The temperature sensor has the advantages of simpler structure, lower cost, better stability, broader measurement range, comparing with the traditional temperature sensor.