Non-Metal Reinforced Lead-Free Composite Solder Fabrication Methods and its Reinforcing Effects to the Suppression of Intermetallic Formation: Short Review

2013 ◽  
Vol 421 ◽  
pp. 260-266 ◽  
Author(s):  
M.A.A. Mohd Salleh ◽  
Stuart McDonald ◽  
Kazuhiro Nogita

To increase the solder joint robustness, researches and studies on composite solder carried out by many researchers in an effort to develop viable lead-free solders which can replace the conventional lead-based solders.This paper reviews the fabrication processes of the lead-free composite solder and its non-metal reinforcing effects to the suppression of intermetallic formation. Most researchers using different solder fabrication methods have found that byadditions of non-metal reinforcement from micron up to nanoparticle size had suppressed the intermetallic compound formations of lead-free composite solders.

2015 ◽  
Vol 830-831 ◽  
pp. 265-269
Author(s):  
Satyanarayan ◽  
K.N. Prabhu

In the present work, the bond strength of Sn-0.7Cu, Sn-0.3Ag-0.7Cu, Sn-2.5Ag-0.5Cu and Sn-3Ag-0.5Cu lead free solders solidified on Cu substrates was experimentally determined. The bond shear test was used to assess the integrity of Sn–Cu and Sn–Ag–Cu lead-free solder alloy drops solidified on smooth and rough Cu substrate surfaces. The increase in the surface roughness of Cu substrates improved the wettability of solders. The wettability was not affected by the Ag content of solders. Solder bonds on smooth surfaces yielded higher shear strength compared to rough surfaces. Fractured surfaces revealed the occurrence of ductile mode of failure on smooth Cu surfaces and a transition ridge on rough Cu surfaces. Though rough Cu substrate improved the wettability of solder alloys, solder bonds were sheared at a lower force leading to decreased shear energy density compared to the smooth Cu surface. A smooth surface finish and the presence of minor amounts of Ag in the alloy improved the integrity of the solder joint. Smoother surface is preferable as it favors failure in the solder matrix.


Author(s):  
Nur Syahirah Mohamad Zaimi ◽  
Mohd Arif Anuar Mohd Salleh ◽  
Mohd Mustafa Al Bakri Abdullah ◽  
Marliza Mostapha ◽  
Romisuhani Ahmad

Materials ◽  
2019 ◽  
Vol 12 (2) ◽  
pp. 289 ◽  
Author(s):  
Meng Zhang ◽  
Ke-ke Zhang ◽  
Fu-peng Huo ◽  
Hui-gai Wang ◽  
Yang Wang

Composite solder is a promising route to improve the properties and reliability of Sn-based lead-free solder. In this study, Cu-coated graphene nanosheets (Cu-GNSs) were synthesized using pyrolysis. Cu-GNSs reinforced Sn2.5Ag0.7Cu0.1RE composite lead-free solders were prepared via powder metallurgy. The size, distribution, and adsorption type of Cu nanoparticles on the GNSs were studied. The relation of the Cu-GNSs content and microstructure to the physical, wettability, and mechanical properties of composite solders was discussed. The results show that Cu nanoparticles (with a mean size of 13 nm) present uniform distribution and effective chemisorptions on the GNS. Microstructural evolution of composite solders is dependent on the addition of Cu-GNSs. With increasing Cu-GNSs addition, β-Sn grains become finer and the eutectic phase proportion becomes larger, while the morphology of the eutectic phase transforms from dispersion to network-type. The improvement of the tensile strength of the composite solder can be attributed to grain refinement and load transfer. While the existence of Cu-GNSs can effectively improve the wettability and slightly change the melting point, it can also lead to the decline of elongation and electrical conductivity of the composite solder.


2016 ◽  
Vol 700 ◽  
pp. 123-131 ◽  
Author(s):  
Rita Mohd Said ◽  
Mohd Arif Anuar Mohd Salleh ◽  
Mohd Nazree Derman ◽  
Mohd Izrul Izwan Ramli ◽  
Norhayanti Mohd Nasir ◽  
...  

This work investigated the effects of 1.0 wt. % TiO2 particles addition into Sn-Cu-Ni solder paste to the growth of the interfacial intermetallic compound (IMC) on Cu substrate after isothermal aging. Sn-Cu-Ni solder paste with TiO2 particles were mechanically mixed to fabricate the composite solder paste. The composite solder paste then reflowed in the reflow oven to form solder joint. The reflowed samples were then isothermally aged 75, 125 and 150 ° C for 24 and 240 h. It was found that the morphology of IMCs changed from scallop-shape to a more uniform planar shape in both Sn-Cu-Ni/Cu joints and Sn-Cu-Ni-TiO2 /Cu joint. Cu6Sn5 and Cu3Sn IMC were identified and grew after prolong aging time and temperature. The IMCs thickness and scallop diameter of composite solder paste were reduced and the growth of IMCs thickness after isothermal aging become slower as compared to unreinforced Sn-Cu-Ni solder paste. It is suggested that TiO2 particles have influenced the evolution and retarded the growth of interfacial IMCs.


2011 ◽  
Vol 133 (3) ◽  
Author(s):  
Tong An ◽  
Fei Qin

The significant difference between failure modes of lead-containing and lead-free solder joints under drop impact loading remains to be not well understood. In this paper, we propose a feasible finite element approach to model the cracking behavior of solder joints under drop impact loading. In the approach, the intermetallic compound layer/solder bulk interface is modeled by the cohesive zone model, and the crack driving force in the intermetallic compound layer is evaluated by computing the energy release rate. The numerical simulation of a board level package under drop impact loading shows that, for the lead-containing Sn37Pb solder joint, the damage in the vicinity of the intermetallic compound layer initiates earlier and is much greater than that in the lead-free Sn3.5Ag solder joint. This damage relieves the stress in the intermetallic compound layer and reduces the crack driving force in it and consequently alleviates the risk of the intermetallic compound layer fracturing.


2012 ◽  
Vol 626 ◽  
pp. 791-796 ◽  
Author(s):  
Mohd Arif Anuar Mohd Salleh ◽  
Muhammad Hafiz Hazizi ◽  
Mohd Mustafa Al Bakri Abdullah ◽  
N.Z. Noriman ◽  
Ramani Mayapan ◽  
...  

Researches and studies on composite solder have been done by many researchers in an effort to develop viable lead-free solders which can replace the conventional lead-based solders as lead is considered as toxic. Solder materials developed by composite approach showed improvement in their properties and importantly it improved their service performance when compared with solder materials developed by other methods. This paper reviews the solder properties of various types of composite lead-free solder that were fabricated via powder metallurgy route. The fabrication processes of the composite solder material by using powder metallurgy route which involved mixing the powder homogeneously, compaction of the mixed powder and sintering the green body were discussed in detail. The types of reinforcements used in order to enhance its properties and the roles of the reinforcement used were also discussed in detail. Properties of a desirable composite solder and the effects of the reinforcement addition to the composite solder microstructure, changes in its wettability and improvement of its mechanical properties were later discussed in this paper. In conclusion, by reviewing various research advances in composite solder material, a solder material with high solder joint reliability at elevated temperature have yet to be found. Thus, a novel composite solder material with higher solder joint reliability at room and elevated temperature was proposed.


2020 ◽  
Vol 2020 ◽  
pp. 1-25
Author(s):  
Shuai Li ◽  
Xingxing Wang ◽  
Zhongying Liu ◽  
Feng Mao ◽  
Yongtao Jiu ◽  
...  

With the miniaturization of solder joints and deterioration of serving environment, much effort had been taken to improve the properties of Sn-based lead-free solders. And the fabrication of Sn-based lead-free composite solder alloys by the addition of nanoparticles is one of the effective ways to enhance the properties. In this paper, the recent research progress on the Sn-based lead-free composite solder alloys is reviewed by summarizing the relevant results in representative ones of Sn-Ag-Cu (SAC), Sn-Bi, and other multielement lead-free composite solder alloys. Specifically speaking, the effect of the added nanoparticles on the evolution of wettability, microstructure morphology, and mechanical properties of Sn-based lead-free composite solder alloys are summarized. It is hoped that this paper could supply some beneficial suggestions in developing the novel Sn-based lead-free composite solder alloys. Additionally, the existed issues and future development trends in the exploitation of new novel Sn-based lead-free composite solder alloys are proposed.


2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Guang Chen ◽  
Yao-Feng Wu

Purpose The purpose of this paper is to investigate the effect of titanium nitride (TiN) on microstructure and composition of 96.5Sn3Ag0.5Cu (SAC305) lead-free solder joints under a large temperature gradient. Design/methodology/approach In this paper, SAC305 lead-free composite solder containing 0.05 Wt.% TiN was prepared by powder metallurgy method. A temperature gradient generator was designed and the corresponding samples were also prepared. The microstructural evolution, internal structure and elemental content of SAC305 and SAC305/TiN solder joints before and after thermal loading were comparatively studied. Findings The experimental results show that the addition of the TiN reinforcing phase can effectively inhibit the diffusion and migration of copper atoms and, therefore, affect the distribution of newly formed Cu-Sn IMC in solder joints under the condition of thermal migration (TM). Compared with the SAC305 solder joint, the interconnection interface and internal structure of the composite solder joint after 600 h of TM are also relatively complete. Originality/value The TiN reinforcing phase is proven effective to mitigate the TM behavior in solder joints under thermal stressing. Specifically, based on the observation and analysis results of microstructure and internal structure of composite solder joint, the TiN particle can change the temperature gradient distribution of the solder joint, so as to suppress the diffusion and migration of Sn and Cu atoms. In addition, the results of Micro-CT and compositional analysis also indicate that the addition of TiN reinforcement is very helpful to maintain the structural integrity and the compositional stability of the solder joint. Different from other ceramic reinforcements, TiN has good thermo- and electro-conductivity and the thermal-electrical performance of composite solder will not be significantly affected by this reinforcement, which is also the main advantage of selecting TiN as the reinforcing phase to prepare composite solder. This study can not only provide preliminary experimental support for the preparation of high reliability lead-free composite solder but also provide a theoretical basis for the subsequent study (such as electro-thermo distribution in solder joints), which has important application significance.


Sign in / Sign up

Export Citation Format

Share Document