纳米颗粒诱导SAC锡球双超声固相互连及其可靠性研究

基于铝合金导电导热性优良，密度比铜小，价格比铜便宜。电子封装中铝合金及其复合材料的广泛使用，以铝代铜的场合越来越多，加之人们对铝电极焊盘免镀镍、银等金属直接钎焊的迫切需要，将铝与铜实现高质量互连已成为当务之急。本项目提出以活性纳米颗粒作为诱导，采用SAC焊锡粉（或球）及双超声能量辅助，实现纳米颗粒诱导SAC焊锡粉（或球）双超声固相低温互连，研究单/双超声下焊点的形成过程和接头服役过程中热可靠性，探索超声固相界面连接机理和复合焊缝形成机理。项目的实施有利于进一步拓宽了固相焊和超声辅助连接技术的应用范围，丰富了超声能场理论，为异材和难焊材料互连提供借鉴，为铝铜及其复合材料在微小界面上实现功能性连接和大型构件上实现结构连接的应用奠定基础。

Based on aluminum alloy excellent conductivity and thermal conductivity, its density was smaller than copper and its price was lower than copper. More and more aluminum alloy and its composite materials were used in electronic packaging, and more and more occasions were used to replace copper with aluminum. In addition, there was an urgent need for direct brazing/soldering of aluminum electrodes (or pads) without nickel and silver etc, the realization of high-quality interconnection of aluminum and copper has become a top priority. In this project, active nanoparticles are used as inducer, SAC solder powder (or ball) and double ultrasonic energy are used to complete low-temperature and solid-phase interconnection of Cu/Al joints induced by nano-particles. The formation process of solder joint and thermal reliability in service processes of joint under single/double ultrasound were studied. The bonding mechanism of solid-phase interface under single/double ultrasound and the composited processing of solder joints were explored. The implementation of the project is conducive to further broadening the application range of solid-state welding and ultrasonic-assisted connection technology, enriching the theory of ultrasonic energy field, and providing reference for the interconnection of different materials and difficult-to-weld materials. It lays a foundation for the application of Al-Cu and its composites to complete functional connection on micro-interface and structural connection on large-scale components.