Synthesis, Characterization, and Thermal Properties of Nanoscale Lead-Free Solders on Multisegmented Metal Nanowires

Abstract

Nanoscale lead-free solders (“nanosolders”) have been synthesized directly onto multisegmented metal nanowires using an electrodeposition method in nanoporous templates. The nanosolders fabricated include tin (Sn), tin/silver (Sn/Ag), and indium (In), and the diameter of the nanosolder nanowires ranges from 30 nm to 200 nm and the length from 1 to 10 μm. The microstructures of the lead-free nanosolders on nanowires have been characterized using optical microscopy and electron microscopy including a field-emission scanning electron microscope (FESEM) and a transmission electron microscope (TEM), along with energy-dispersive X-ray spectroscopy (EDS). Thermal properties of lead-free nanosolders on nanowires were characterized using a temperature-programmable furnace tube under a controlled atmosphere. It was found that nitrogen plays an important role in the nanosolder reflow process. The effect of base layer, barrier layer, and wetting layer on nanosolder reflow was studied, and an optimal nanowire nanosolder system with effective barrier and wetting layers was obtained. A liquid phase-based solder reflow process was developed, in which the nanosolder nanowires were assembled in a liquid medium and solder joints were formed between nanowires.

From Microjoining to Nanojoining

“…This is illustrated in the following example on reflow soldering of multisegmented metal nanowires [17,32,34,35]. Multisegmented metal (such as Sn/Au/Ni) nanowires were fabricated using an electrodeposition method in nanoporous templates [32,17,34,35].…”

“…This is illustrated in the following example on reflow soldering of multisegmented metal nanowires [17,32,34,35]. Multisegmented metal (such as Sn/Au/Ni) nanowires were fabricated using an electrodeposition method in nanoporous templates [32,17,34,35]. In one example, Tin was grown on the ends of Au nanowires with Ni/Au as under-layers (Ni as a diffusion barrier and Au as wetting layer) and then the Sn/Au/Ni coated Au nanowires were reflow soldered together in a liquid medium [35].…”

“…Fig. (13) shows reflow soldering of magnetically self-organized Sn-Au-Ni-Au-Sn multisegmented nanowires in a liquid medium [17,36]. Nanoink imprinting is another strategy gaining interest because it is an economical and highly functional technology for microscale patterning of metallic nanoparticle traces [46][47][48].…”

Femtosecond laser welded nanostructures and plasmonic devices

“…This is illustrated in the following example on reflow soldering of multisegmented metal nanowires. 11,21 Multisegmented metal (such as Sn/Au/Ni) nanowires were fabricated using an electrodeposition method in nanoporous templates. In one example, Tin was grown on the ends of Au nanowires with Ni/Au as under-layers (Ni as a diffusion barrier and Au as wetting layer) and then the Sn/Au/Ni coated Au nanowires were reflow soldered together in a liquid medium.…”

Molecular dynamics simulation of joining process of Ag-Au nanowires and mechanical properties of the hybrid nanojoint

“…1,2 For joining of nanomaterials, several methods have been demonstrated, such as electron and ion beam deposition, [3][4][5] laser irradiation, 6,7 cold welding 8 and soldering. 9,10 One primary application of nanojoining is to improve the electronic properties of metal nanowires (NWs) -based transparent electrodes.…”