【作者】 李毅；

【导师】 王涛；

【作者基本信息】 电子科技大学 ， 光学工程， 2014， 硕士

【摘要】 近年来,基于钽酸锂(LiTaO3)晶体材料的热释电红外探测器具有抗辐照能力强、环境适应性好、灵敏度高、生产一致性好等特点,世界各航天大国纷纷采用热释电红外探测器替代原有的热敏电阻型红外探测器。迄今为止,国际上对钽酸锂热释电探测器的研究已经广泛开展,但国内对此的研究尚有不足,探测器结构设计还不成熟,对敏感材料的研究也有待提高,例如钽酸锂敏感材料的制备和减薄。本文首先对热释电探测器的工作原理进行了阐述和讨论,对敏感元不同备选材料进行了详细的介绍和分析,综合各方面因素采用钽酸锂作为探测器的敏感材料。重点研究了热释电探测器的电学、热学和力学性能,并结合大量的仿真和分析得出了理论上最佳的设计值,此外还开展了钽酸锂的减薄工艺实验,制备了厚度为28μm的钽酸锂晶片。具体工作如下:1、基于集总参数模型,提出了三种不同的支撑结构(既:双腿、四腿、五腿),通过改变敏感材料的厚度,对不同支撑结构下热释电探测器的电压响应、噪声、探测率等电学性能进行分析和讨论,得到探测器电学性能随结构和敏感元厚度变化的数据和趋势,为敏感材料参数的选择和器件的结构优化提供了依据;2、基于有限元分析软件,针对几种热释电探测器结构的热学和力学性能进行仿真,分析了不同敏感材料厚度、支撑结构以及桥腿高度对热释电探测器的热学和力学性能影响,综合考虑以上性能提出了五腿结构、敏感层20μm的结构模型;3、基于电学、热学和力学性能的讨论,对钽酸锂晶体的减薄进行了较为深入的研究,通过不断改进实验方法和工艺步骤,制备出性能较好的钽酸锂晶片。更多还原

【Abstract】 In recent years, pyroelectric infrared detectors based on lithium tantalate(LiTaO3,a crystalline solid) were adopted in space exploration instead of thermistor infrared detector, because they have such advantages as strong radioresistance, good environmental adaptability, high sensitivity, good consistency of production, etc.So far, researches on lithium tantalate pyroelectronic infrared detectors have been widely carried out in the world. While domestic researches are comparatively rare due to the immature structure design of detector and the lack of researches on sensitive materials, such as the fabrication and reduction of lithium tantalate sensitive material.In this thesis, the working principle of pyroelectric infrared detectors has been discussed, and different sensing element alternative materials were analyzed, and lithium tantalate as sensitive material of detectors of various factors have been adopted.And the properties of pyroelectronic detectors in electricity, thermology and mechanics have been researched combined with plenty of simulations and analyses. Additionally,an experiment of reduction of lithium tantalate chip has been conducted, and a 28-um lithium tantalate chip has been obtained. The specific work is as follow:1.Based on the lumped parameter model, three different supporting structures,including two legs, four legs and five legs, have been proposed. By changing the thickness of sensitive material, the voltage response, noise and detectivity of the pyroelectronic detectors under different supporting structure have been studied, which provide a foundation for selection of sensitive material parameter and structural optimization of instruments.2.Based on the software of finite element analysis, the simulations aiming at the thermal and mechanical properties of several pyroelectronic detectors have been done,and the influence of on the mechanical and thermal properties of pyroelectric detectors have been analyzed. Taking all those affecting factors into account, a 20-um material thickness was preferable and the five legs structure was chosen.3.Based on the discussion of the properties in electricity, thermology and mechanism, reduction of lithium tantalate chip have been done. By improving experiment methods and processing steps, a preferable lithium tantalate wafer is obtained.更多还原