Effects of Ga addition on microstructure and properties of Sn–0.5Ag–0.7Cu solder

J Mater Sci: Mater Electron

Liu

2014

Self Cite

This work was focused on the influence of Ga on the thermal properties, microstructural evolution and interfacial morphology with aging treatment at 150°C of low-silver Sn-0.5Ag-0.7Cu (SAC) lead-free solder. The melting temperature of the SAC-Ga solder was decreased owing to the low melting point element Ga and the formations of intermetallic compound (IMC) and growth at the interfaces of SAC/Cu and SAC-0.5Ga/Cu were studied for different aging time ranging from 0 to 720 h. The results indicated that for both solders, the thickness of the IMC increased with aging time prolonging. However, compared with the interface of SAC/Cu, the thickness of the interface of SAC-Ga/Cu was obviously suppressed and the growing speed was slowed down, which may be attributed to the decreased activity of copper atoms by Ga addition, so that the SAC-Ga solder showed relatively planar-like IMC instead of scallop-like at the interface.

Section: Interfacial Microstructurementioning

confidence: 99%

Section: Introductionmentioning

confidence: 96%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Investigation on the intermetallic compound layer growth of Sn–0.5Ag–0.7Cu–xGa/Cu solder joints during isothermal aging

Luo

J Mater Sci: Mater Electron

Liu

2014

Self Cite

“…Ga can be easily enriched on the surface of the Sn-Pb solder liquid surface and form a dense protective film to improve the oxidation resistance of the solder [6,7]. Similarly, in this paper, Ga is added into the solder to ameliorate such problems.…”

Section: Introductionmentioning

confidence: 95%

Effect of Ga on the Inoxidizability and Wettability of Sn-0.5Ag-0.7Cu-0.05Pr Solder

Advances in Materials Science and Engineering

Luo

et al. 2017

The effect of trace amount of Ga on the inoxidizability and wettability of Sn-0.5Ag-0.7Cu-0.05Pr solders was investigated systematically by means of microstructure characterizations. The results indicate that the wettability and oxidation resistance properties are remarkably improved with addition of trace amount of Ga. Moreover, it is observed that the trace amount of Ga in Sn-0.5Ag-0.7Cu-0.05Pr solders refines the matrix microstructure. The relationship between wettability and oxidation resistance was put into deep study. And Ga was found to be enriched on the surface of the molten solder, which benefited the properties correspondingly. The results of this study can stimulate the use of low-silver Sn-Ag-Cu-Pr solders for various applications.

“…The previous researches [8,9] showed that the melting point of SAC solders declined, meanwhile, the wettability of them enhanced with the addition of Ga. But taking account of the increasing requirement of reducing Ag content, a small amount addition of Ga cannot compensate for the negative effects of the reduction of Ag.…”

Section: Introductionmentioning

confidence: 99%

Effects of trace amount praseodymium and neodymium on microstructure and mechanical properties of Sn–0.3Ag–0.7Cu–0.5Ga solder

Han

J Mater Sci: Mater Electron

Yang

et al. 2015

The effects of trace mount of rare earth elements Pr and Nd addition on Sn-0.3Ag-0.7Cu-0.5Ga lead free solder were investigated by observation of microstructure and the morphology of interface layer, as well as the test of shearing strength of the solder joints. The results show that the microstructure of the solder matrix can be optimized by appropriate addition of Pr and Nd, but the scalloped and ''region-like'' compounds (IMCs) appear in the solder matrix with excessive Pr and Nd addition respectively which may result in the stress concentration and become the birthplace of the cracks. The behavior of absorption of rare earth elements can retard the interface reaction between solder and Cu substrate, refine the morphology of the interface layer. The shearing strength of the solder joints can be enhanced better with appropriate addition of Pr than Nd by improvement of nucleation rate and control of growth rate of the grains near the interface layer.