Alternative transducer and optical pumping scheme for nanoscale thermal metrology and imaging

用于纳米级热计量和成像的替代传感器和光泵浦方案

• 批准号: 2315077
• 负责人: Peijun Guo
• 金额: $ 40.29万
• 依托单位: Yale University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-09-01 至 2026-08-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2315077&HistoricalAwards=false
• 关键词: Alternative; transducer; optical; pumping; scheme

Heat dissipation is intrinsic to technologies ranging from micro- and power-electronics to energy-storage devices and thermoelectrics. The ability to characterize and understand thermal transport processes can help regulate the flow of heat and improve device functionality, efficiency, and stability, especially for those made of materials with poor thermal conductivities. Nonetheless, measuring thermal transport in low thermal-conductivity materials at a high spatial resolution is still challenging. A new approach is proposed here, in which the heat flow will be directly imaged by a high-speed camera with spatial resolution down to hundreds of nanometers. The proposed approach is laser-based, hence non-contact, and will take advantage of organic semiconducting materials, which are abundant and ubiquitously used in organic light-emitting diodes and displays. The organic semiconductors will serve as local temperature reporters of materials underneath, whose thermal conductivity can be assessed by observing how quickly the temperature of the organic semiconductor varies in time. The project will provide extensive training opportunities to graduate and undergraduate students in the construction and modification of comprehensive optical measurement systems with high spatial and temporal resolution. K-12 students from local public high schools will gain understanding and experience in state-of-the-art thermal metrology experiments.Defects, grain boundaries, among other types of inhomogeneities are characteristics of materials that are not single crystals or epitaxial films. To understand the influence of such imperfections on heat transport in emerging energy-related materials, the team will explore organic semiconductors as an alternative type of transducer for optical pump-probe thermoreflectance measurements. The morphology, optical properties, and thermal transport properties of several prototypical organic semiconductors will be thoroughly investigated over a wide temperature range. Meanwhile, a time-resolved, wide-field optical imaging setup will be constructed, which will permit efficient thermal excitation of organic transducers and their accurate temperature monitoring with nanosecond time resolution. The team will perform proof-of-concept experiments to spatiotemporally imaging the flow of heat in heterogeneous energy materials and in prototypical two-dimensional ferromagnetic materials. It is expected that the alternative transducer and imaging technique proposed here can complement the existing thermoreflectance techniques for the investigation of thermal transport properties of a wide range of technologically important materials used for energy conversion and storage, optoelectronics, and beyond. The ability to remove the transducer after their use is a useful feature for measuring unreproducible or high-value samples, and for failure analysis and quality control of semiconductor chips.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

热量耗散是从微电和电源到能量储存设备和热电学的技术固有的。表征和理解热运输过程的能力可以帮助调节热量的流动并提高设备功能，效率和稳定性，尤其是对于由具有较差导热率的材料制成的功能。尽管如此，在高空间分辨率下测量低热传导材料中的热传输仍然具有挑战性。这里提出了一种新方法，其中将通过高速摄像头直接成像，其空间分辨率低至数百纳米。所提出的方法是基于激光的，因此是非接触的，它将利用有机半导体材料，这些材料丰富且无限于有机发光二极管和显示器。有机半导体将用作下面的材料的局部温度报告，可以通过观察有机半导体的温度在时间上变化的速度来评估其热导率。该项目将为毕业和本科生提供广泛的培训机会，以建造和修改具有高空间和时间分辨率的综合光学测量系统。来自当地公立高中的K-12学生将获得最先进的热量测量实验的理解和经验。缺陷，晶界，除其他类型的不均匀性外，是不是单个晶体或外部膜的材料的特征。为了了解此类缺陷对新兴能源相关材料中热传输的影响，该团队将探索有机半导体，作为用于光学泵探针热射型测量值的替代换能器的替代类型。几种原型有机半导体的形态，光学特性和热传输性能将在较宽的温度范围内进行彻底研究。同时，将构建一个时间分辨，宽视野光学成像设置，这将允许通过纳秒时间分辨率进行有机换能器的有效热激发及其准确的温度监测。该团队将执行概念验证实验，以时空成像异质能量材料中的热量以及原型的二维铁磁材料。可以预期，此处提出的替代传感器和成像技术可以补充现有的热融合技术，以调查用于用于能量转换和存储，光电货量及其他地区的各种技术重要材料的热传输性能。在使用后删除传感器的能力是测量不可再生或高价值样本的有用功能，以及对半导体芯片的失败分析和质量控制。该奖项反映了NSF的法定任务，并被认为是值得通过基金会的知识智能和更广泛影响的评估来通过评估来获得支持的。