Activation energy for Cu-Sn intermetallic in CNT-reinforced Sn-1.0Ag-0.5Cu solder

2019 ◽  
Vol 32 (2) ◽  
pp. 65-72
Author(s):  
Ramani Mayappan ◽  
Amirah Salleh ◽  
Nurul Atiqah Tokiran ◽  
N.A. Awang
Keyword(s):  
Activation Energy ◽  
Carbon Nanotube ◽  
Solder Joint ◽  
Design Methodology ◽  
Lead Free ◽  
Content Type ◽  
Intermetallic Growth ◽  
Soldering Time ◽  
Lead Free Solders ◽  
Sac Solder

Purpose The purpose of this study is to investigate the addition of 0.05 Wt.% carbon nanotube (CNT) into the Sn-1.0Ag-0.5Cu (SAC) solder on the intermetallic (IMC) growth. Lead-based solders play an important role in a variety of applications in electronic industries. Due to the toxicity of the lead in the solder, lead-free solders were proposed to replace the lead-based solders. Sn-Ag-Cu solder family is one of the lead-free solders, which are proposed and considered as a potential replacement. Unfortunately, the Sn-Ag-Cu solder faces some reliability problems because of the formation of the thick intermetallic compounds. So the retardation of intermetallic growth is prime important. Design/methodology/approach The solder joint was aged under liquid state aging with soldering time from 1 to 60 min. Findings Two types of intermetallics, which are Cu6Sn5 and Cu3Sn were observed under a scanning electron microscope. The morphology of Cu6Sn5 intermetallic transformed from scallop to planar type as the soldering time increases. The addition of carbon nanotube into the SAC solder has retarded the Cu6Sn5 intermetallic growth rate by increasing its activation energy from 97.86 to 101.45 kJ/mol. Furthermore, the activation energy for the Cu3Sn growth has increased from 102.10 to 104.23 kJ/mol. Originality/value The increase in the activation energy indicates that the growth of the intermetallics was slower. This implies that the addition of carbon nanotube increases the reliability of the solder joint and are suitable for microelectronics applications.

Hardness testing of lead-free solders: a review

2017 ◽  
Vol 29 (4) ◽  
pp. 203-224 ◽  
Author(s):  
Muhamad Zamri Yahaya ◽  
Ahmad Azmin Mohamad
Keyword(s):  
Design Methodology ◽  
Vickers Microhardness ◽  
Measurement Techniques ◽  
Lead Free ◽  
Hardness Testing ◽  
Testing Methods ◽  
Content Type ◽  
Test Configuration ◽  
Recent Trends ◽  
Lead Free Solders

Purpose This paper aims to cover the recent (2010-2016) techniques for carrying out hardness evaluation on lead-free solders. Details testing configuration/design were compiled and discussed accordingly to each of the measurement techniques: Vickers microhardness, Brinell microhardness and nanoindentation. Design/methodology/approach A brief introduction on lead-free solders and the concept of hardness testing has been described at the beginning of the review. Equipment setup, capabilities, test configuration and outcomes were presented for each technique and discussed in parallel along with the case studies from selected articles. Findings Comparison, outcomes and insight regarding each of the methods were highlighted to observe the recent trends, scientific challenges, limitations and probable breakthroughs of the particular hardness testing methods. Originality/value The compilation of latest reports, technical setup plus with the critics and perception from the authors are the main key value in this review. This provides an in-depth understanding and guidance for conducting hardness evaluation on lead-free solders.

Accurate composition dependent thermo mechanical lifetime estimation of hour glass type solder joint in electronic assemblies

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Leonid Anatolevich Olenev ◽  
Rafina Rafkatovna Zakieva ◽  
Nina Nikolaevna Smirnova ◽  
Rustem Adamovich Shichiyakh ◽  
Kirill Aleksandrovich Ershov ◽  
...  
Keyword(s):  
Finite Element ◽  
Chemical Composition ◽  
Solder Joint ◽  
Design Methodology ◽  
Lifetime Estimation ◽  
Creep Tests ◽  
Content Type ◽  
Element Simulation ◽  
Glass Type ◽  
Electronic Assemblies

Purpose This study aims to present a more accurate lifetime prediction model considering solder chemical composition. Design/methodology/approach Thermal cycling and standard creep tests as well as finite element simulation were used. Findings The study found lower error in the solder joint lifetime evaluation. The higher the Ag content is, the higher the lifetime is achieved. Originality/value It is confirmed.

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

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.

Experimental and numerical fatigue life assessment of SAC305 solders subjected to combined temperature and harmonic vibration loadings

2020 ◽  
Vol 32 (3) ◽  
pp. 181-187
Author(s):  
Mohammad Gharaibeh
Keyword(s):  
Fatigue Life ◽  
Compound Layer ◽  
Harmonic Vibration ◽  
Life Assessment ◽  
Lead Free ◽  
Intermetallic Compound Layer ◽  
Loading Test ◽  
Content Type ◽  
Vibration Loading ◽  
Lead Free Solders

Purpose This paper aims to investigate the fatigue life performance of SAC305 ball grid array solders under combined temperature and harmonic vibration loading conditions. Design/methodology/approach Fatigue tests were performed using a sine dwell with resonance tracking vibration and temperature loading experiment. Finite element stress analysis was also performed to help in understanding the observed failure trends. Findings Fatigue test results showed that the lead-free solders tend to fail quickly in higher temperatures and higher vibration loading test conditions. The failure analysis results revealed that in low temperatures, the solder cracks are initiated and propagated at the package side. However, in high temperatures, the cracks are observed at the board side of the interconnect. In all conditions, the cracks are propagated throughout the intermetallic compound layer. Originality/value In the published literature, there is a lack of data in the area of fatigue assessment of lead-free solders under combined temperature and vibration loadings. This paper provides useful insights into combined thermal/vibration fatigue, i.e. reliability behavior of lead-free solder joint types.

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

2018 ◽  
Vol 30 (1) ◽  
pp. 1-13 ◽  
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.

Intermetallic growth between lead-free solders and palladium

2003 ◽  
Vol 32 (11) ◽  
pp. 1209-1213 ◽  
Author(s):  
Gaurav Sharma ◽  
C. M. Eichfeld ◽  
S. E. Mohney
Keyword(s):  
Lead Free ◽  
Intermetallic Growth ◽  
Lead Free Solders

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
Keyword(s):  
Intermetallic Compound ◽  
Solder Joint ◽  
Composite Solder ◽  
Short Review ◽  
Lead Free ◽  
Nanoparticle Size ◽  
Intermetallic Formation ◽  
Reinforcing Effects ◽  
Lead Free Solders

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.

The size effect on intermetallic microstructure evolution of critical solder joints for flip chip assemblies

2015 ◽  
Vol 27 (4) ◽  
pp. 178-184 ◽  
Author(s):  
Ye Tian ◽  
Justin Chow ◽  
Xi Liu ◽  
Suresh K. Sitaraman
Keyword(s):  
Solder Joint ◽  
Design Methodology ◽  
Growth Process ◽  
Flip Chip ◽  
Solder Bump ◽  
Solder Joints ◽  
Solder Matrix ◽  
Industrial Practice ◽  
Content Type ◽  
Flip Chips

Purpose – The purpose of this paper is to study the intermetallic compound (IMC) thickness, composition and morphology in 100-μm pitch and 200-μm pitch Sn–Ag–Cu (SAC305) flip-chip assemblies after bump reflow and assembly reflow. In particular, emphasis is placed on the effect of solder joint size on the interfacial IMCs between metal pads and solder matrix. Design/methodology/approach – This work uses 100-μm pitch and 200-μm pitch silicon flip chips with nickel (Ni) pads and stand-off height of approximately 45 and 90 μm, respectively, assembled on substrates with copper (Cu) pads. The IMCs evolution in solder joints was investigated during reflow by using 100- and 200-μm pitch flip-chip assemblies. Findings – After bump reflow, the joints size controls the IMC composition and dominant IMC type as well as IMC thickness and also influences the dominant IMC morphology. After assembly reflow, the cross-reaction of the pad metallurgies promotes the dominant IMC transformation and shape coarsened on the Ni pad interface for smaller joints and promotes a great number of new dominate IMC growth on the Ni pad interface in larger joints. On the Cu pad interface, many small voids formed in the IMC in larger joints, but were not observed in smaller joints, combined with the drawing of the IMC growth process. Originality/value – With continued advances in microelectronics, it is anticipated that next-generation microelectronic assemblies will require a reduction of the flip-chip solder bump pitch to 100 μm or less from the current industrial practice of 130 to150 μm. This work shows that as the packaging size reduced with the solder joint interconnection, the solder size becomes an important factor in the intermetallic composition as well as morphology and thickness after reflow.

A review: lead free solder and its wettability properties

2016 ◽  
Vol 28 (3) ◽  
pp. 125-132 ◽  
Author(s):  
Ervina Efzan Mhd Noor ◽  
Nur Faziera Mhd Nasir ◽  
Siti Rabiatul Aisya Idris
Keyword(s):  
Surface Tension ◽  
Contact Angle ◽  
Electronic Packaging ◽  
Design Methodology ◽  
Lead Free ◽  
Lead Free Solder ◽  
Research Papers ◽  
Basic Principles ◽  
Content Type ◽  
Free Solder

Purpose The purpose of this paper is to publish on the review of the lead free solder for electronic packaging. This involved the basic principles of the solder, the lead solder and its legislation and the lead free solder with its mechanism. In addition, this paper also reviews on the lead free solder characteristics that focused on its wettability. Design/methodology/approach This paper approach on the review of the solder wettability on the surface. It reviews on the solder especially on the contact angle and surface tension that is covered under the wettability of the solder. Findings This paper also reviews on the lead free solder characteristics that focused on its wettability. Originality/value This paper summarized finding from other researchers. The authors collect and summarize the useful data from other papers or journals. It is to create an understanding for the reader by discussion from the others research papers findings.

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