Uncooled Silicon Germanium Oxide Microbolometers with Metasurface for Multispectral Infrared Imaging

用于多光谱红外成像的具有超表面的非冷却硅锗氧化物微测辐射热计

• 批准号: 1509589
• 负责人: Mahmoud Almasri
• 金额: $ 33.95万
• 依托单位: University of Missouri-Columbia
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-09-15 至 2019-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1509589&HistoricalAwards=false
• 关键词: Uncooled; Silicon; Germanium; Oxide; Microbolometers

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.

摘要：许多研究表明，与基于强度的假彩色或灰度图像相比，彩色图像可以更快、更准确地理解场景、反应时间和识别目标。捕获红外光谱分布（颜色）提供更多信息，提高对比度和目标识别，提供比传统夜视图像更好的态势感知。然而，目前的制冷多色红外技术需要昂贵的低温冷却系统才能运行，而非制冷多色技术复杂且昂贵。为了解决这个问题，该研究项目将以一种新的架构将超表面集成到非冷却红外（IR）微辐射热计上。超表面选择性吸收将与具有多个堆叠微辐射热计的像素中的fabry - p<s:1>谐振腔相结合，在不同的光谱窗口中提供高红外吸收，同时保持90%以上的填充因子。这将使入射辐射在其强度之外的属性，包括其光谱分布，得以解决。超表面将允许微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，便携式非冷却多波段红外探测器具有广泛的应用，如汽车安全，医疗保健，监视和地雷探测。该项目将为研究生、本科生和高中生提供全面的教育培训和课程开发。拓展工作将集中在林肯大学的客座讲座上，林肯大学是一所地区性的HBCU，并从STEM教育中代表性不足的群体中招募学生。此外，该项目还将通过推进综合、多学科、多校区的研究生培养，进一步推进科学教育。本项目的研究目标是通过集成热隔离双级像素结构、具有工程辐射特性的超表面和基于非晶Si-Ge-O的传感层，建立非冷却红外微热计的设计和微制造框架。这将创建一个非冷却的多波段红外（IR）微辐射热计，其中来自不同波段的图像被融合成一个高分辨率的多色图像。通过合成超表面来完成多波段操作，以确定两个微测辐射热计的吸收/透射/反射特性。本课题主要研究长波红外波段光谱含量的测量。入射辐射的振幅分为两个波段，对应于两个微辐射热计。这将允许在不事先知道其温度的情况下确定辐射表面的温度。法布里-普氏腔和表面共振的结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。使用超表面作为吸收剂，可以进一步探索微辐射热计设计的热特性，以提高性能。将建立严格的耦合电磁和热模型来预测器件的性能。这些装置将被制造和表征，以识别噪声源和优化降噪。研究的目的是了解集成超表面和微辐射热计的电磁/热和噪声效应，阐明法布里-帕姆罗特与超表面共振之间的相互作用，并建立两波段微辐射热计的制作原理。这将提供更好的检测技术，使未来一代更小、更轻、成本更低的多色热成像系统成为可能，这些系统消耗更少的功率，并能在环境温度下工作。