A novel method of reducing melting temperatures in SnAg and SnCu solder alloys

• Published in: Journal of materials science. Materials in electronics Vol. 22; no. 3; pp. 281 - 285
• Main Authors: Chukka, Rami N., Telu, Suresh, NRMR, Bhargava, Chen, Lang
• Format: Journal Article
• Language: English
• Published: Boston Springer US 01.03.2011; Springer; Springer Nature B.V
• Subjects: Alloys; Applied sciences; Brazing. Soldering; Characterization and Evaluation of Materials; Chemistry and Materials Science; Condensed matter: structure, mechanical and thermal properties; Cross-disciplinary physics: materials science; rheology; Electronics; Equations of state, phase equilibria, and phase transitions; Exact sciences and technology; Integrated circuits; Integrated circuits by function (including memories and processors); Joining, thermal cutting: metallurgical aspects; Materials Science; Melting; Metals. Metallurgy; Nanomaterials; Nanopowders; Nanoscale materials and structures: fabrication and characterization; Nanostructure; Optical and Electronic Materials; Physics; Semiconductor electronics. Microelectronics. Optoelectronics. Solid state devices; Soldering; Solders; Solid-liquid transitions; Specific phase transitions; Tin base alloys; Solder Alloy; High Energy Ball Mill; Melting Point Depression; Eutectic Alloy; Melting Property; Wave soldering; Differential scanning calorimetry; Eutectic alloy; Melting; Molten state; Nanoparticle; Tin alloy; Solder metal; Nanostructure; Integrated circuit bonding; Attrition mill; Casting; Nanometer scale; Soldered joint; Size effect; Lead free soldering; Lead free solder; Modem; Copper; Soldering; Melting point
• ISSN: 0957-4522; 1573-482X
• DOI: 10.1007/s10854-010-0128-5

With the increasing use of lead-free solder alloys in modern electronics, low melting materials are often required to protect the heat-sensitive parts during soldering operation. Alloy systems based on Sn/Cu/Ag offer more reliable solutions and address the current problems involved with soldering process. Nanoparticles melt relatively at low temperatures compared to their bulk counter parts and we introduce a robust method of synthesizing nanoscale solder pastes for wave soldering applications. Nanoparticles of Sn-3.5Ag and Sn-0.7Cu alloys were prepared with stir casting followed by mechanical attrition. The size dependent melting properties of the eutectic alloys were studied by differential scanning calorimetry technique and the results showed a reduction of 4.7 and 5.0 °C melting temperatures in the alloys when reduced from bulk to 92 nm and 96 nm sizes respectively. The nanosize effects were also theoretically calculated and compared with experimental data.