复合添加Ga,Al,Ag对Sn-9Zn钎料性能的影响

Effects of Ga,Al and Ag multi-additions on wetting properties of Sn-9Zn lead-free solders

采用润湿平衡法研究了合金元素Ga,Al,Ag复合添加对Sn-9Zn钎料润湿性的影响.结果表明,Ga,Al,Ag的最佳添加量分别为0.2,0.002,0.25(质量分数,%);添加合金元素后钎料的高温抗氧化性能显著提高.俄歇电子能谱分析表明,Sn-9Zn-0.2Ga-0.002Al-0.25Ag钎料表面Al高度富集并形成一层致密的氧化膜,可阻挡氧向液态钎料内部扩散,减少钎料的氧化.Sn-9Zn-0.2Ga-0.002Al-0.25Ag钎料与Cu/Ni/Au基板之间的金属间化合物由一层平坦的AuZn3和颗粒状的AuAgZn2化合物组成.另外,微焊点力学试验表明,采用Sn-9Zn-0.2Ga-0.002Al-0.25Ag钎料时,电子元器件与基板间微焊点的力学性能比Sn-9Zn钎料略有提高.

Wetting balance method is used to evaluate the effects of Ga,Al,and Ag multi-additions on the wetting property of Sn-9Zn lead-free solders.Results show that the optimal loading of Ga,Al,and Ag is 0.2 wt.%,0.002 wt.%,and 0.25 wt.% respectively.The intermetallics formed at the interface of Sn-9Zn-0.2Ga-0.002Al-0.25Ag solder and Cu/Ni/Au substrate is investigated by scanning electron microscope(SEM)and energy dispersive spectroscopy(EDS)analysis.SEM images illustrate that two portions,a planar AuZn3 layer and an additional continuous scallop-like AuAgZn2 layer,formed in the intermetallics.Meanwhile,X-ray photoelectron spectroscopy(XPS)and Auger electron spectroscopy(AES)analysis on the surface components of Sn-9Zn-0.2Ga-0.002Al-0.25Ag solder indicate that Al aggregates at the surface of the solder in the form of Al2O3 protective film which prevents the solder from further oxidation and improves the wettability in consequence.