Wetting characteristics of Sn-5Sb-CuNiAg lead-free solders on the copper substrate

Purpose The purpose of this paper is to investigate the wetting behaviors of Sn-5Sb-CuNiAg solders on copper substrates in different soldering processes and the effects of alloying elements on the wettability. Design/methodology/approach Sn-5Sb-CuNiAg solder balls (750 µm in diameter) were spread and wetted on 40 × 40 × 1 mm copper plates, in different fluxes, soldering temperatures and time. The contact angles were obtained by a home-made measuring instrument. The samples were polished and deep etched before analyzed by scanning electron microscopy. Energy dispersive X-ray spectroscopy was used to identify the composition of the joints. Findings The effects of different soldering processes and alloying elements on the wetting behaviors of Sn-5Sb-CuNiAg solders on copper substrates were calculated and expounded. The rosin-based flux could effectively remove oxidation layers and improve the wettability of Sn-5Sb-CuNiAg solders. Then with the increase of soldering temperature and time, the contact angles decreased gradually. The soldering processes suited for Sn-5Sb-CuNiAg solders were RMA218, 280°C and 30 s. Considered the effects of alloying elements, the wettability of Sn-5Sb-0.5Cu-0.1Ni-0.5Ag was relatively favorable on copper substrates. Besides, Ni could accumulate at the solder/Cu interface and form a jagged (Cu,Ni)6Sn5 IMC. Originality/value This work was carried out with our handmade experiment equipment and the production of the quinary lead-free solder alloy used in wetting tests belongs to us. The investigated Sn-5Sb-CuNiAg alloys exhibited higher melting point and preferable wettability, that was one of the candidates for high-temperature lead-free solders to replace high-Pb solders, and applied extremely to high temperature and frequency working environments of the third-generation semiconductors components, with a greater potential research and development value.

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Investigations of the wetting behaviors of Zn–25Sn, Zn–25Sn–XPr and Zn–25Sn–YAl high temperature lead free solders in air and Ar ambient

Journal of Alloys and Compounds ◽

10.1016/j.jallcom.2015.06.185 ◽

2015 ◽

Vol 646 ◽

pp. 852-858 ◽

Cited By ~ 14

Author(s):

Xi Niu ◽

Kwang-Lung Lin

Keyword(s):

High Temperature ◽

Lead Free ◽

Lead Free Solders ◽

Wetting Behaviors

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Shear Strength and Dsc Analysis of High-Temperature Solders

Archives of Metallurgy and Materials ◽

10.2478/amm-2013-0031 ◽

2013 ◽

Vol 58 (2) ◽

pp. 529-533 ◽

Cited By ~ 5

Author(s):

R. Koleňák ◽

M. Martinkovič ◽

M. Koleňáková

Keyword(s):

Shear Strength ◽

High Temperature ◽

Lead Free ◽

Dsc Analysis ◽

Ultrasonic Activation ◽

Metallic Substrates ◽

Cu Substrate ◽

Lead Free Solders

The work is devoted to the study of shear strength of soldered joints fabricated by use of high-temperature solders of types Bi-11Ag, Au-20Sn, Sn-5Sb, Zn-4Al, Pb-5Sn, and Pb-10Sn. The shear strength was determined on metallic substrates made of Cu, Ni, and Ag. The strength of joints fabricated by use of flux and that of joints fabricated by use of ultrasonic activation without flux was compared. The obtained results have shown that in case of soldering by use of ultrasound (UT), higher shear strength of soldered joints was achieved with most solders. The highest shear strength by use of UT was achieved with an Au-20Sn joint fabricated on copper, namely up to 195 MPa. The lowest average values were achieved with Pb-based solders (Pb-5Sn and Pb-10Sn). The shear strength values of these solders used on Cu substrate varied from 24 to 27 MPa. DSC analysis was performed to determine the melting interval of lead-free solders.

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Reliability of High Temperature and Vibration in Sn3.5Ag and Sn0.7Cu Lead-free Solders

Journal of the Microelectronics and Packaging Society ◽

10.6117/kmeps.2012.19.3.031 ◽

2012 ◽

Vol 19 (3) ◽

pp. 31-36 ◽

Cited By ~ 1

Author(s):

Yong-Ho Ko ◽

Taek-Soo Kim ◽

Young-Kyu Lee ◽

Sehoo Yoo ◽

Chang-Woo Lee

Keyword(s):

High Temperature ◽

Lead Free ◽

Lead Free Solders

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High Melting Temperature Lead Free Solder for Die Attach Application

International Symposium on Microelectronics ◽

10.4071/isom-2011-tp4-paper1 ◽

2011 ◽

Vol 2011 (1) ◽

pp. 000322-000326

Author(s):

Jianxing Li ◽

Daniel Lau ◽

Pingliang Tu ◽

Andrew Delano ◽

Brian Knight

Keyword(s):

Thermal Conductivity ◽

Copper Substrate ◽

Process Condition ◽

Lead Free ◽

Test Results ◽

Melt Temperature ◽

Die Attach ◽

Free Solder ◽

Lead Free Solders ◽

Board Level

Two lead free solders were developed for die attach application. The bismuth based solder has a melt temperature of 271C and thermal conductivity of 18W/mK. The zinc based solder has a melt temperature of 337C and thermal conductivity of 85W/mK. Both solders have acceptable wetting on bare copper and nickel plated copper substrate, could be processed using modified high lead solder process condition and survived 260C board level reflow simulation. This paper discusses the solder material properties, and presents the die attach process and reliability test results in a manufacturing environment.

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

Soldering & Surface Mount Technology ◽

10.1108/ssmt-10-2019-0030 ◽

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.

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