Interfacial Reactions of Si Die Attachment with Zn-Sn and Au-20Sn High Temperature Lead-Free Solders on Cu Substrates

ABSTRACTRecently, it was reported that adding Zn to solder was an effective way for reducing the formation of both Cu3Sn and Cu6Sn5 and inhibiting Kirkendall voids formation. The objective of this study is to investigate this Zn effect in detail. Three Sn-xZn solders (x = 0.5, 0.7, and 2 wt. %) were reacted with Cu substrates at 250°J for 2-10 mins. A slight variation in the Zn concentration changed the reaction product formed at the interface. When the Zn concentration was low (x = 0.5 wt. %), the reaction product was Cu6Sn5. At high Zn concentration (x = 2 wt. %), the reaction product became Cu5Zn8. When Zn concentration was in-between (x = 0.7 wt. %), Cu6Sn5 and CuZn co-existed. The above findings are explained using the Cu–Sn–Zn phase diagram. The implication is that the type of compound forms at the interface can be controlled by adjusting the Zn concentration of the Sn-based solders.

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Interfacial reactions and mechanism properties between SAC 405 and SACNG lead-free solders with Au/Ni(P)/Cu substrates reflowed by CO2 laser

2009 4th International Microsystems, Packaging, Assembly and Circuits Technology Conference ◽

10.1109/impact.2009.5382136 ◽

2009 ◽

Author(s):

Shao-cheng Lo ◽

Yu-Ping Hsieh ◽

Yee-wen Yen

Keyword(s):

Interfacial Reactions ◽

Lead Free ◽

Cu Substrates ◽

Lead Free Solders

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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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Interfacial reactions between Sn–8Zn–3Bi–xNi lead-free solders and Cu substrate during isothermal aging

Materials Chemistry and Physics ◽

10.1016/j.matchemphys.2010.05.028 ◽

2010 ◽

Vol 123 (2-3) ◽

pp. 629-633 ◽

Cited By ~ 13

Author(s):

Lijuan Liu ◽

Wei Zhou ◽

Baoling Li ◽

Ping Wu

Keyword(s):

Isothermal Aging ◽

Interfacial Reactions ◽

Lead Free ◽

Cu Substrate ◽

Lead Free Solders

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Interfacial reactions of Sn–58Bi and Sn–0.7Cu lead-free solders with Alloy 42 substrate

Microelectronics Reliability ◽

10.1016/j.microrel.2013.09.003 ◽

2014 ◽

Vol 54 (1) ◽

pp. 233-238 ◽

Cited By ~ 8

Author(s):

Yee-Wen Yen ◽

Ruo-Syun Syu ◽

Chih-Ming Chen ◽

Chien-Chung Jao ◽

Guan-Da Chen

Keyword(s):

Interfacial Reactions ◽

Lead Free ◽

Lead Free Solders

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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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