Structured illumination with thermal imaging (SI-TI): A dynamically reconfigurable metrology for parallelized thermal transport characterization

• Published in: Applied physics reviews 2022-06, Vol.9 (2)
• Main Authors: Zheng, Qiye, Chalise, Divya, Jia, Mingxin, Zeng, Yuqiang, Zeng, Minxiang, Saeidi-Javash, Mortaza, Tanvir, Ali N. M., Uahengo, Gottlieb, Kaur, Sumanjeet, Garay, Javier E., Luo, Tengfei, Zhang, Yanliang, Prasher, Ravi S., Dames, Chris
• Format: Article
• Language: English
• ISSN: 1931-9401; 1931-9401
• DOI: 10.1063/5.0079842

The recent push for the “materials by design” paradigm requires synergistic integration of scalable computation, synthesis, and characterization. Among these, techniques for efficient measurement of thermal transport can be a bottleneck limiting the experimental database size, especially for diverse materials with a range of roughness, porosity, and anisotropy. Traditional contact thermal measurements have challenges with throughput and the lack of spatially resolvable property mapping, while non-contact pump-probe laser methods generally need mirror smooth sample surfaces and also require serial raster scanning to achieve property mapping. Here, we present structured illumination with thermal imaging (SI-TI), a new thermal characterization tool based on parallelized all-optical heating and thermometry. Experiments on representative dense and porous bulk materials as well as a 3D printed thermoelectric thick film (∼50 μm) demonstrate that SI-TI (1) enables paralleled measurement of multiple regions and samples without raster scanning; (2) can dynamically adjust the heating pattern purely in software, to optimize the measurement sensitivity in different directions for anisotropic materials; and (3) can tolerate rough (∼3 μm) and scratched sample surfaces. This work highlights a new avenue in adaptivity and throughput for thermal characterization of diverse materials.