The Effect of Aging on Microstructures Evolution and Shear Behaviors in Lead-free Solder Joint

This paper proposes the high reliable design method for lead-free solder joint on metal substrate on chip component. First, the crack propagation analysis method for estimating rupture life of solder joint was constructed. And then, the effect of material properties of insulating layer on metal substrate and solder joint shape for rupture life of solder joint was evaluated using crack propagation analysis. As the result, the relation between young’s modulus of insulating layer and rupture life was indicated quantitatively. Also, the relation of filet length for rupture life of solder joint was evaluated. Secondary, evaluation method of heat dissipation for metal substrate was proposed. Because thermal conductivity of insulating layer affects temperature rise of heating device. And, the relation between thermal conductivity of insulating layer and temperature rise of heating device was indicated.

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Vibration Fatigue Reliability of Lead and Lead-Free Solder Joint by FORM/SORM

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.345-346.1393 ◽

2007 ◽

Vol 345-346 ◽

pp. 1393-1396

Author(s):

Ouk Sub Lee ◽

Man Jae Hur ◽

Yeon Chang Park ◽

Dong Hyeok Kim

Keyword(s):

Solder Joint ◽

Failure Probability ◽

Lead Free ◽

Lead Free Solder ◽

Fatigue Reliability ◽

Probability Models ◽

First Order ◽

Reliability Method ◽

Vibration Fatigue ◽

Free Solder

It is well-known that the vibration significantly affect the life of solder joint. In this paper, the effects of the vibration on the failure probability of the solder joint are studied by using the failure probability models such as the First Order Reliability Method (FORM) and the Second Order Reliability Method (SORM). The accuracies of the results are estimated by a help of the Monte Carlo Simulation (MCS). The reliability of the lead and the lead-free solder joint was also evaluated. The reliability of lead-free solder joint is found to be higher than that of lead solder joint.

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Solder Joint Reliability of Sn-Cu and Sn-Ag-Cu Lead-Free Solder Alloys Solidified on Copper Substrates with Different Surface Roughnesses

Materials Science Forum ◽

10.4028/www.scientific.net/msf.830-831.265 ◽

2015 ◽

Vol 830-831 ◽

pp. 265-269

Author(s):

Satyanarayan ◽

K.N. Prabhu

Keyword(s):

Solder Joint ◽

Solder Matrix ◽

Lead Free ◽

Lead Free Solder ◽

Solder Alloys ◽

Cu Substrate ◽

Cu Substrates ◽

Free Solder ◽

Substrate Surfaces ◽

Lead Free Solders

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.

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Loading Mixity on the Interfacial Failure Mode in Lead-Free Solder Joint

Lead-free Solders ◽

10.1520/stp49325s ◽

2011 ◽

pp. 121-121-18

Author(s):

Feng Gao ◽

Jianping Jing ◽

Frank Z. Liang ◽

Richard L. Williams ◽

Jianmin Qu

Keyword(s):

Solder Joint ◽

Failure Mode ◽

Lead Free ◽

Lead Free Solder ◽

Interfacial Failure ◽

Free Solder

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Influence of Substrate Surface Finish Metallurgy on Lead-Free Solder Joint Microstructure with Implications for Board-Level Reliability

Journal of Electronic Materials ◽

10.1007/s11664-020-08013-0 ◽

2020 ◽

Vol 49 (5) ◽

pp. 3251-3258

Author(s):

Marion Branch Kelly ◽

Tapabrata Maity ◽

A. R. Nazmus Sakib ◽

D. R. Frear ◽

Nikhilesh Chawla

Keyword(s):

Solder Joint ◽

Substrate Surface ◽

Lead Free ◽

Lead Free Solder ◽

Joint Microstructure ◽

Solder Joint Microstructure ◽

Influence Of Substrate ◽

Free Solder ◽

Board Level ◽

Board Level Reliability

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The Effects of Electromigration to the Solder Joint Formation: A Comparison Between 99.3Sn-0.7Cu and 96.5Sn-3.0Ag-0.5Cu Lead Free Solder

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.622-623.195 ◽

2012 ◽

Vol 622-623 ◽

pp. 195-199 ◽

Cited By ~ 2

Author(s):

M.A.A. Mohd Salleh ◽

A.R. Nik Nurhidayatul Suhada ◽

Flora Somidin ◽

Rafezi Ahmad Khairel ◽

C.S. Lee ◽

...

Keyword(s):

Solder Joint ◽

Room Temperature ◽

Solder Joints ◽

Research Work ◽

Cathode Region ◽

Lead Free ◽

Lead Free Solder ◽

Joint Formation ◽

Current Stress ◽

Free Solder

Electromigration effects on the solder joint formation of 99.3Sn-0.7Cu and 96.5Sn-3.0Ag-0.5Cu lead-free solder with Cu electroplated Ni layer wire were investigated. The electromigration effects on the solder joints were studied after current density stressing at 1 x 103 A/cm2 in room temperature for 0 h, 120 h, and 240 h. The research work found that intermetallic compound (IMC) formation on the joint is increases for both solders with longer period of current stress applied. Higher IMC thickness growth in 99.3Sn-0.7Cu solder joint compared to 99.3Sn-0.7Cu is detected and both anode regions of the solder joints show higher IMC thickness growth compared to cathode region. Experimental results show 99.3Sn-0.7Cu solder joint is more prone to failure under current stress compared to 96.5Sn-3.0Ag-0.5Cu solder joint with thicker IMC which translates to higher brittleness.

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Influence of an Immersion Gold Plating Layer on Reliability of a Lead-Free Solder Joint

MATERIALS TRANSACTIONS ◽

10.2320/matertrans.46.2725 ◽

2005 ◽

Vol 46 (12) ◽

pp. 2725-2729 ◽

Cited By ~ 5

Author(s):

Ikuo Shohji ◽

Hiroki Goto ◽

Kiyotomo Nakamura ◽

Toshikazu Ookubo

Keyword(s):

Solder Joint ◽

Lead Free ◽

Lead Free Solder ◽

Gold Plating ◽

Free Solder ◽

Plating Layer

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SAC–xTiO2 nano-reinforced lead-free solder joint characterizations in ultra-fine package assembly

Soldering & Surface Mount Technology ◽

10.1108/ssmt-04-2017-0011 ◽

2018 ◽

Vol 30 (1) ◽

pp. 1-13 ◽

Cited By ~ 12

Author(s):

Fakhrozi Che Ani ◽

Azman Jalar ◽

Abdullah Aziz Saad ◽

Chu Yee Khor ◽

Roslina Ismail ◽

...

Keyword(s):

Electron Microscope ◽

Solder Joint ◽

Solder Joints ◽

Ion Beam ◽

Lead Free ◽

Lead Free Solder ◽

Solder Paste ◽

Content Type ◽

X Ray ◽

Free Solder

Purpose This paper aims to investigate the characteristics of ultra-fine lead-free solder joints reinforced with TiO2 nanoparticles in an electronic assembly. Design/methodology/approach This study focused on the microstructure and quality of solder joints. Various percentages of TiO2 nanoparticles were mixed with a lead-free Sn-3.5Ag-0.7Cu solder paste. This new form of nano-reinforced lead-free solder paste was used to assemble a miniature package consisting of an ultra-fine capacitor on a printed circuit board by means of a reflow soldering process. The microstructure and the fillet height were investigated using a focused ion beam, a high-resolution transmission electron microscope system equipped with an energy dispersive X-ray spectrometer (EDS), and a field emission scanning electron microscope coupled with an EDS and X-ray diffraction machine. Findings The experimental results revealed that the intermetallic compound with the lowest thickness was produced by the nano-reinforced solder with a TiO2 content of 0.05 Wt.%. Increasing the TiO2 content to 0.15 Wt.% led to an improvement in the fillet height. The characteristics of the solder joint fulfilled the reliability requirements of the IPC standards. Practical implications This study provides engineers with a profound understanding of the characteristics of ultra-fine nano-reinforced solder joint packages in the microelectronics industry. Originality/value The findings are expected to provide proper guidelines and references with regard to the manufacture of miniaturized electronic packages. This study also explored the effects of TiO2 on the microstructure and the fillet height of ultra-fine capacitors.

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