Ioffe Institute, Saint-Petersburg 194021, Russia.
Sensors (Basel). 2023 Mar 30;23(7):3590. doi: 10.3390/s23073590.
This paper is a review of recent applications of a laser photothermal mirage technique for sensing and measuring the thermal resistance of joint layers in modern electronic devices. A straightforward theoretical model of the interfacial thermal resistance based on the formation of a thin intermediate layer between jointed solids is described. It was experimentally shown that thermal properties of solder layers cannot be evaluated simply on the base of averaging the thermal properties of solder components. The review presents the laser thermal wave methodology for measuring thermal parameters of soldered and adhesively bonded joints. The developed theoretical model makes it possible to carry out a quantitative estimation of local thermal conductivities of joints and their thermal resistances by fitting theoretical results with experimental data obtained by the laser beam deflection method. The joints made with lead-containing and lead-free solders were studied. The anomalous distribution of thermal properties in the solder layer is explained by the diffusion of various atoms detected by energy dispersive X-ray spectroscopy. The laser beam deflection method made it possible to reveal a strong influence of the surface pretreatment quality on the interfacial thermal resistance.
本文综述了激光光热幻影技术在现代电子器件中用于传感和测量连接层热阻的最新应用。描述了一种基于在连接固体之间形成薄中间层的界面热阻的简单理论模型。实验表明，不能简单地通过平均焊点组件的热性能来评估焊料层的热性能。综述介绍了用于测量焊接和胶粘连接热参数的激光热波方法。所开发的理论模型通过将理论结果与通过激光束偏转法获得的实验数据拟合，使得对连接的局部热导率及其热阻进行定量估计成为可能。研究了含铅和无铅焊料制成的接头。通过能谱分析检测到的各种原子的扩散，解释了焊点层热性能的异常分布。激光束偏转法能够揭示表面预处理质量对界面热阻的强烈影响。
