Uncooled Silicon Germanium Oxide Microbolometers with Metasurface for Multispectral Infrared Imaging

摘要标题：非制冷硅锗氧化物微测辐射热计与Metasurface多光谱红外成像摘要：许多研究表明，彩色图像导致更快，更准确的场景理解，反应时间和对象识别比强度为基础的假彩色或灰度图像。捕获红外光谱分布（颜色）提供了更多的信息，提高了对比度和目标识别，这比传统的夜视图像提供了更好的态势感知。然而，目前的冷却式红外线技术需要昂贵的低温冷却系统来操作，而非冷却式红外线技术复杂且昂贵。为了解决这个问题，该研究项目将在一种新的架构中将超表面集成到非制冷红外（IR）微测辐射热计上。超颖表面选择性吸收将与具有多个堆叠微测辐射热计的像素中的法布里-珀罗谐振腔相结合，以在不同光谱窗口中提供高IR吸收，同时保持90%以上的填充因子。这将使入射辐射的属性超出其强度，包括其光谱分布，被解决。超表面将允许微测辐射热计的电和热性能与其辐射特性部分解耦。由此产生的技术将导致低成本，便携式非制冷多波段红外探测器，具有广泛的应用，如汽车安全，医疗保健，监控和地雷探测。该项目将为研究生、本科生和高中生提供全面的教育培训，并编制课程。外展工作将集中在林肯大学的客座讲座上，这是一个地区性的HBCU，并从STEM教育中代表性不足的群体中招募学生。该项目的研究目标是通过将热隔离双层像素结构、具有工程辐射特性的超表面和非晶Si-Ge-O基传感层相结合，建立非制冷红外微测辐射热计的设计和微制造框架。这将创建一个非制冷的多波段红外（IR）微测辐射热计，其中来自不同波段的图像融合成一个具有高分辨率的单通道图像。通过合成超颖表面来确定两个微测辐射热计的吸收/透射/反射特性来完成多频带操作。该研究项目的重点是测量长波红外范围内的光谱内容。入射辐射的幅度被分成对应于两个微测辐射热计的两个频带。这将允许在事先不知道其温度的情况下确定辐射表面的温度。Fabry-Pérot腔和表面谐振的组合为设计像素的光谱响应提供了多个自由度，因此不需要牺牲填充因子。使用超颖表面作为吸收体允许进一步探索微测辐射热计设计的热特性以改善性能。将建立严格的电磁和热耦合模型来预测器件的性能。这些设备将被制造和表征，以识别噪声源并优化降噪。研究的目的是产生知识的电磁/热和噪声效应集成的超颖表面和微测辐射热计，阐明法布里-珀罗和超颖表面谐振之间的相互作用，并建立两个波段的微测辐射热计的制造原则。这将提供更好的检测技术，使下一代更小，更轻，低成本的光热成像系统，消耗更少的功率，并在环境温度下工作。

Abstract Title: Uncooled Silicon Germanium Oxide Microbolometers with Metasurface for Multispectral Infrared ImagingAbstract:Many studies have shown that color imagery leads to faster and more accurate scene understanding, reaction time and object identification than intensity-based false color or grayscale imagery. Capturing the spectral distribution (color) in the infrared provides more information, improving contrast and object-identification, which provides better situational awareness than conventional night vision imagery. However, the current cooled multicolor infrared technology requires an expensive cryogenic cooling system for operation, while uncooled multicolor technology is complex and expensive. To address this issue, the research project will integrate metasurfaces onto uncooled infrared (IR) microbolometers in a novel architecture. The metasurface selective absorption will be combined with the Fabry-Pérot resonant cavity in a pixel with multiple stacked microbolometers, to provide high IR absorption in different spectral windows while maintaining a fill factor over 90%. This will allow attributes of incident radiation beyond its intensity, including its spectral distribution, to be resolved. The metasurfaces will allow the electrical and thermal performance of the microbolometer to be partially decoupled from its radiative properties. The resulting technology will lead to low cost, portable uncooled multiband IR detectors with a broad range of applications such as automotive safety, healthcare, surveillance, and landmine detection. The project will provide comprehensive educational training to graduate, undergraduate and high school students, and curriculum development. The outreach effort will be focused on guest lectures at Lincoln University, a regional HBCU, and recruiting students from underrepresented groups in STEM education. In addition, the project will also further scientific education by advancing integrated, multidiplinary, multicampus postgraduate training.The research goal of this project is to establish the design and microfabrication frameworks for uncooled IR microbolometers by integrating a thermally isolated dual-level pixel architecture, a metasurface with engineered radiative properties, and an amorphous Si-Ge-O based sensing layer. This will create an uncooled multiband infrared (IR) microbolometer where the images from different bands are fused into a single multicolor image with high resolution. The multiband operation is accomplished by synthesizing metasurfaces to determine the absorption/transmission/reflection properties of the two microbolometers. The research project focuses on measuring the spectral content in the long wave IR range. The amplitude of the incident radiation is divided into two bands corresponding to the two microbolometers. This will allow the temperature of a radiating surface to be determined without knowing its temperature beforehand. The combination of Fabry-Pérot cavity and surface resonances provides multiple degrees of freedom for designing the spectral response of the pixel so the fill factor does not need to be sacrificed. The use of the metasurfaces as an absorber allows further exploration of the thermal characteristics of microbolometer design for improved performance. Rigorous coupled electromagnetic and thermal models will be built to predict the performance of the devices. These devices will be fabricated and characterized to identify sources of noise and optimize for noise reduction. The research objective is to generate knowledge about the electromagnetic/thermal and noise effects of integrating the metasurface and microboleter, elucidate the interaction between the Fabry-Pérot and metasurface resonance, and establish fabrication principles for the two-band microbolometer. This will provide better detection technology that will enable a future generation of smaller, lighter, low cost multicolor thermal imaging systems that consume less power and operates at ambient temperature.