电子元器件低温焊接技术的研究进展

Research Progress of Low Temperature Welding Technology for Electronic Components

低温焊接技术是实现电子元器件多级封装和高温服役的关键技术之一。针对高可靠电子元器件封装对于低温连接、高温服役的焊接技术的需求,从材料制备工艺、焊料熔点变化和焊接工艺技术等方面对纳米金属颗粒低温烧结、瞬时液相低温烧结和颗粒增强低温焊接(烧结)工艺进行了综述。纳米金属颗粒低温烧结工艺形成的焊点稳定服役温度高于300℃,其制备复杂,烧结工艺对焊膏的依赖性较强,进一步优化焊料配方及其烧结工艺为其主流研究方向。瞬时液相低温烧结工艺,通过形成高熔点金属间化合物焊点提高其耐高温性能,其内部组分及耐高温性能对焊接工艺依赖性较强,明确焊点组分以及耐高温性能、焊接工艺为其主流研究方向。颗粒增强低温焊接(烧结)工艺,通过形成高温富集相与金属间化合物提升熔点,回流焊后熔点提升较小,明确其熔点与组分的变化规律为其研究重点。

Low temperature welding technology is one of the key technologies to realize multistage packaging and high temperature service of electronic components.According to the requirements of welding technology for low-temperature connection and high-temperature service in high reliable electronic component packaging,low temperature sintering of nano-metal particles,instantaneous liquid phase low temperature sintering and particle reinforced low temperature welding(sintering)are reviewed from the aspects of material preparation process,solder melting point change and welding process technology.Low temperature sintering process of nano-metal particles,forming solder joint stable service temperature is higher than 300℃.Its preparation is complex,and the sintering process is highly dependent on the solder.Further optimization of the solder formulation and sintering process is the mainstream of research direction.Transient liquid phase low-temperature sintering process can improve its high-temperature resistance by forming high melting point intermetallic compound solder joints.Its internal components and high-temperature resistance are strongly dependent on the welding process,and it is the mainstream direction of its research to clarify the solder joint components,high temperature resistance properties and welding process.The particle reinforced low-temperature welding(sintering)process can improve the melting point by forming high-temperature enriched phase and intermetallic compound,and the melting point after reflow welding is small.The research focus is to clarify the change law of its melting point and composition.