Morphology and Shear Strength of Lead-Free Solder Joints with Sn3.0Ag0.5Cu Solder Paste Reinforced with Ceramic Nanoparticles

Abstract

To date, additions of different oxide nanoparticles is one of the most widespread procedures to improve the mechanical properties of metals and metal alloys. This research deals with the effect of minor ceramic nanoparticle additions (SiO 2 , TiO 2 and ZrO 2 ) on the microstructure and mechanical properties of Cu/solder/Cu joints. The reinforced Sn3.0Ag0.5Cu (SAC305) solder alloy with 0.5 wt.% and 1.0 wt.% of ceramic nanoparticles was prepared through mechanically stirring. The microstructure of as-solidified Cu/solder/ Cu joints was studied using scanning electron microscopy. The additions of ceramic nanoparticles suppressed the growth of the intermetallic compound layer Cu 6 Sn 5 at the interface solder/Cu and improved the microstructure of the joints. Furthermore, measurements of mechanical properties showed improved shear strength of Cu/composite solder/Cu joints compared to joints with unreinforced solder. This fact related to all investigated ceramic nanoinclusions and should be attributed to the adsorption of nanoparticles on the grain surface during solidification. However, this effect is less pronounced on increasing the nanoinclusion content from 0.5 wt.% to 1.0 wt.% due to agglomeration of nanoparticles. Moreover, a comparison analysis showed that the most beneficial influence was obtained by minor additions of SiO 2 nanoparticles into the SAC305 solder alloy.

Nanocomposite SAC solders: morphology, electrical and mechanical properties of Sn–3.8Ag–0.7Cu solders by adding Co nanoparticles

“…9), while the calculated average thickness of the entire Cu 6 Sn 5 /Cu 3 Sn layer at the interface was about 3.6 µm ( Table 2). This is in agreement with our recent studies of the Cu 3 Sn/Cu 6 Sn 5 IMCs layer at the interface of SAC305/Cu solder joints [32]. Addition of nanoCo leads to substantial changes in the morphology of the IMC layer at the interface (Fig.…”

Nanocomposite SAC Solders: The Effect of Adding Ni and Ni-Sn Nanoparticles on Morphology and Mechanical Properties of Sn-3.0Ag-0.5Cu Solders

“…Similar to our previous studies dealing with nanocomposite SAC solder joints with metal and ceramic nanoadditions, 8,9 a Cu 6 Sn 5 /Cu 3 Sn double layer was observed at the solder/Cu interface. It was found that Ni atoms were incorporated into the Cu 6 Sn 5 crystals, both in the bulk solder and in the interfacial layer, while no regions with either pure Ni or Ni-Sn IMCs could be seen in the joints.…”

“…For instance, a paste and flux mixing method was applied to prepare solders in paste form or as nanocomposite flux-solder mixture, respectively. 7,8,13,14 A conventional planar flow casting 9,15 as well as a roll bonding method 16 have been used to fabricate nanocomposite solder ribbons. The mixing methods are the most popular ones due to the relatively simple experimental procedure; however, during the reflow process the NPs tend to move with the flux, and it is very difficult to estimate the amount of nanoinclusions actually remaining in the solder.…”

Microstructure and Electro-Physical Properties of Sn-3.0Ag-0.5Cu Nanocomposite Solder Reinforced with Ni Nanoparticles in the Melting-Solidification Temperature Range

“…The increasing scientific interest for Sn-based nanocomposite alloys with small additions of various metals, [1][2][3][4] oxides [5][6][7][8] and carbon [9][10][11][12] in nanosized form relates to the possible application of these materials as an alternative to commercial lead-free solders. As pointed out in two literature reviews, [13,14] improved mechanical properties and a reinforced microstructure of solder joints using nanocomposite Sn-Ag-Cu (SAC) alloys compared to those without nanoinclusions, revealed new possibilities for the development of currently used commercial lead-free solders.…”