This paper reviewed the wetting properties of solder for microelectronic packaging. The recent demand for high-density packaging has highlighted the need for a sophisticated and improved solder for the miniaturization of electronics. The wetting properties of molten solder on a substrate, which provides successful soldering and reliable solder joints, is one of the most critical properties for the reliability of components in electronic devices because poor wetting can degrade the reliability of the solder. Therefore, the solder must have good wettability to achieve better solderability. The most common testing method is the wetting balance test known as a Meniscograph. During a wetting test, the analysis can be conducted by calculating the wetting force between the molten solder and substrate as a function of time. In addition, the surface tension and wetting time, which are known as the zero cross time of each sample, are obtained from the respective wetting curves. This paper discusses the wetting balance test, including its principle, parameters, experimental procedure, and analysis of the result from the wetting curve. In addition, this paper introduces the recent advances in the wetting property of solder, such as a nano-reinforced composite solder through the addition of 0.05% of nano-sized La₂O₃ to the solder matrix, which has resulting in an improved wetting time.

中文翻译：

---

通过润湿平衡测试对焊料的润湿性进行综述，以用于最新的先进微电子封装

本文综述了微电子封装用焊料的润湿特性。最近对高密度封装的需求突显了对用于电子设备小型化的精密且改进的焊料的需求。提供成功的焊接和可靠的焊点的熔融焊料在基板上的润湿特性是电子设备中组件可靠性最关键的特性之一，因为不良的润湿会降低焊料的可靠性。因此，焊料必须具有良好的润湿性以实现更好的可焊性。最常见的测试方法是润湿平衡测试，即Meniscograph。在润湿测试过程中，可以通过计算熔融焊料和基材之间的润湿力随时间变化来进行分析。此外，从各自的润湿曲线获得表面张力和润湿时间，即每个样品的零交叉时间。本文讨论了润湿平衡测试，包括其原理，参数，实验步骤以及对润湿曲线结果的分析。此外，本文还介绍了通过添加0.05％的纳米La来提高焊料润湿性的最新进展，例如纳米增强复合焊料。在焊料基体中加入₂ O ₃，从而缩短了润湿时间。