蓝宝石光纤端面上ZnO薄膜的温变特性

Temperature - dependent properties of ZnO film deposited on sapphire fiber ends

为了能利用半导体材料ZnO对光谱曲线随温度变化而移动的原理设计一种光纤温度传感器,因此有必要对生长在光纤端面上的ZnO材料的温变特性的进行研究。基于ZnO材料的测温原理,利用电子束蒸发技术在蓝宝石光纤端面上生长ZnO薄膜,并设计了一种具有低插入损耗的光纤检测系统用于光学性能的分析。光谱测试结果显示,蒸镀在蓝宝石光纤端面上的ZnO薄膜具有陡峭的光学吸收边,随着温度的升高(室温～450℃),ZnO薄膜的禁带宽度减小,吸收边向长波长方向移动,符合半导体材料的温变特性。同时随着温度的升高,平均的透射率有一定的减小。ZnO薄膜温变特性的研究,将为进一步研制以ZnO镀膜为敏感材料的新型光纤温度传感器打下良好的基础。

In order to fabricate fiber - optic temperature sensors based on ZnO film, it is important to study the temperature - dependent optical properties of ZnO materials deposited on fiber ends. In this paper, ZnO thin film was grown on sapphire fiber ends by electron -beam evaporation （EBV） and a novel fiber- optic measurement system was designed to analyze the optical properties based on the temperature measurement principle of ZnO materials. When the temperature increases （room temperature to 450℃ ） , the band gap decreases, the average transmittivity decreases slightly, and the absorption edge has a red shift, in accordance with the temperature - dependent properties of semiconductors. These properties will supply crucial evidences to further fabricate a fiber -optic temperature sensor based on semiconductor ZnO, utilizing the influence of optical absorption spectra in different temperatures.