基于MEMS技术的非制冷红外成像系统的研究

发布时间：2018-05-15 15:27

本文选题：MEMS + 非制冷　；参考：《苏州大学》2015年硕士论文

【摘要】：随着时代的发展,在社会生活的各个领域中,红外成像技术都有了广泛的应用,不仅仅包括了传统的军事、医疗等区域,在新兴的定位系统、新能源、车载系统等领域,红外成像技术的应用也在与日俱增。特别是非制冷红外成像系统,人们将更多的目光和关注投入到它的高可靠性、低成本以及高性能上。本论文的研究重点在于非制冷红外成像技术上,其核心原理在于采用微机电系统(MEMS,Micro-Electro-Mechanical System)传感器和光信号系统读出。并基于上述原理研发了,光-机械悬臂梁MEMS镂空氮化硅薄膜红外探测器,并通过MEMS技术手段,搭建了非制冷红外成像系统,取得了一系列技术领先的成像技术结果。主要成果如下列举:1、本论文的重中之重是红外芯片的器件制作,且在设计时采用了SiNx/Al双材料组合加工工艺,该种材料组合也是本论文的创新点和亮点。2、本文使用新的算法,设计了最新型自支撑无硅衬底和热隔离变形叠加的红外焦平面阵列(FPA),与此同时,对其进行了性能优化和热动力学建模。获取了新型FPA整体的、成套的优化方法和标准结构。通过与使用通常牺牲层机结构的MEMS红外传感器结构比较,该结构使探测器的辐射利用率有效的提高了一个层次,并且在制作工艺流程上进行了有效的优化和简化。基于上述理论,考虑到制作工艺的宽容度,对设计单元的像素尺寸为50um*50um、阵列个数为240*240。3、重新设计和开发了一系列用于单层氮化硅(SiNx)镂空薄膜悬臂梁FPA的标准制作流程和制作工艺。特别是控制盲元率、整体硅腐蚀工艺、低应力氮化硅膜(SiNx)的应力控制等关键技术重新开发并进行了深入系统的研究,制作了变形叠加热隔离FPA结构和基于自支撑无衬底结构的制作。本文的主要创新之处便在于此,使用新型工艺标准,使FPA阵列器件的盲元率控制在10%以下。4、使用了新的两种结构的FPA,和改进后的FPA光学读出方法,组件了使用MEMS技术的非制冷红外成像系统装置,采集了一系列室外物体、人体、集成电路板等一系列静态和动态热成像图像。采集到了FPA像素尺寸为50um*50um、阵列个数为240*240的芯片系统性能关键参考数据—噪声等效温度差(NETD)降低到了300mK,该类技术和成果已达到同期国内、国际的领先水平。
[Abstract]:With the development of the times, infrared imaging technology has been widely used in various fields of social life, including not only traditional military, medical and other areas, but also emerging positioning systems, new energy sources, vehicle-borne systems, and so on. Infrared imaging technology is also increasing in application. Especially uncooled infrared imaging system, people will pay more attention to its high reliability, low cost and high performance. This paper focuses on uncooled infrared imaging technology, the core principle of which is the use of MEMS micro-electro-mechanical system sensors and optical signal system readout. Based on the above principle, the photo-mechanical cantilever MEMS hollowed-out silicon nitride thin film infrared detector is developed, and the uncooled infrared imaging system is built by means of MEMS technology, and a series of advanced imaging results are obtained. The main achievements are listed as follows: 1. The most important thing of this thesis is the device fabrication of infrared chip, and the SiNx/Al binomial combination process is adopted in the design. This kind of material combination is also the innovation and bright spot of this paper. The new algorithm is used in this paper. A novel self-supporting silicon free substrate and thermal isolated deformation superposition infrared focal plane array (IRFPA) is designed. At the same time, the performance optimization and thermodynamics modeling are carried out. The whole and complete set of optimization method and standard structure of new FPA are obtained. Compared with the conventional MEMS infrared sensor structure, the structure improves the radiation efficiency of the detector effectively, and optimizes and simplifies the fabrication process. Based on the above theory and taking into account the fabrication technology's tolerance, the pixel size of the design unit is 50um / 50um and the number of arrays is 240U / 240.3. A series of standard fabrication processes and fabrication techniques for single-layer silicon nitride (SiNx) hollow thin film cantilever beam FPA are redesigned and developed. In particular, the key techniques of controlling blind element rate, silicon corrosion process and stress control of low stress silicon nitride film are redeveloped and systematically studied. The deformation superposition thermal isolation FPA structure and the self-supporting non-substrate structure are fabricated. The main innovation of this paper is the use of a new process standard to control the blind cell rate of FPA array devices below 10%. The new two structures of FPAs and the improved FPA optical readout method are used. The uncooled infrared imaging system with MEMS technology is used to collect a series of static and dynamic thermal imaging images of outdoor objects, human body, integrated circuit board and so on. The key reference data for the performance of the chip system whose pixel size of FPA is 50 umum and array number is 240 have been collected and reduced to 300mK. this kind of technology and achievement has reached the domestic and international leading level in the same period.
【学位授予单位】：苏州大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TN215

【相似文献】