The above graph shows temperature of Sn0.3Ag0.7Cux In alloy as a function of indi-um weight percentage. Initially with no traces of Indium, the solidus temperature & liquidus temperature are 219.40̊C and 241.70̊C. It clearly shows that the temperature range goes wider as the concentration of indium is increased [6]. This is not a cost effective solution as indium is very costly.
Titanium oxide nano particles addition led to temperature changing from 217 to 217.64 degree Celsius [7]. Zinc oxide bearing SAC had temperature of about 222.16
High Temperature Electronics
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degree celsius when zinc was about 0.5% by weight [8]. From this it can be conclud-ed that there no major effect on melting temperature.
2.2.2 Wettability
It is the ability of …show more content…
They can grow upto several microns and have excellent electrical conductivity. Their growth can be re-tarded by adding 0.5% Zn, using reflowed tin or hot tin dip. Reflowed tin is a tech-nique that involves reheating a part above the melting temperature of tin after it has been electroplated with tin. Hot tin Dip is a process in which a part is dipped into a bath of molten tin above 450 F. This creates a thin layer at the interface of the base material & tin.
3.2 Voids
The voids can be removed by adding sintered silver foil that is already coated with chromium and gold. On reaction a uniform layer is formed between Ag/Sn & Sn/Au.
3.3 Reduction in Melting Point
Further reduction in melting point can be made by adding more of the rare earth ele-ments into Sn-Ag-Cu solder.
3.4 Calculation of melting Temperature
(Given)
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3.5 State of the Art
The trend is shifting towards lead free solders with different base materials hypo eu-tectic Bi-Ag alloys are preferred based on liquidus temperature in comparison to PbSn solders. Zn-Al eutectic systems alloyed with Mg, Ge ,Ga ,Sn, Sb, Bi may serve interesting topics for …show more content…
Kanlayasiri, M. Mongkolwongrojn, and T. Ariga, “Influence of indium addition on characteristics of Sn-0.3Ag-0.7Cu solder alloy,” Journal of Alloys & Compounds, vol. 485, no. 1-2, pp. 225–230, 2009.
[7] L.W. Lin, J.M. Song, Y. S. Lai, Y. T. Chiu,N.C.Lee, and J. Y. Uan, “Alloying modification of Sn-Ag-Cu solders by manganese and titanium,” Microelectronics Reliability, Vol.49,no.3, pp235-241,2009.
[8] A. Fawzy, S. A. Fayek, M. Sobhy, E. Nassr, M. M. Mousa, and G. Saad, “Tensil -Creep characteristics of Sn−3.5Ag−0.5Cu(SAC355) solder reinforced with nano-metric ZnO Particles”, Materials Science and Engineering A, vol. 603, pp. 1-10, 2014.
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[9] C. M. T. Law, C. M. L. Wu, D. Q. Yu, L. Wang, and J. K. L. Lai, “Microstructure, Solderability & growth of intermetallic compounds of Sn-Ag-Cu-RE lead-free solder alloys”, Journal of Electronic Materials, vol. 35, no. 1, pp. 89–93, 2006.
[10] L. Zhang, X. Y. Fan, Y. H. Guo, and C. W. He, “Properties enhancement of SnAgCu solders containing rare earth element Yb”, Materials & Design, Vol. 57, pp. 646–651, 2014.
[11] L. C. Tsao, S. Y. Chang, C. I. Lee, W. H. Sun, and C. H. Huang, “Effects of nano Al2O3 additions on microstructure development and hardness of Sn3.5Ag0.5Cu solder,” Materials and Design, vol. 31, no. 10, pp. 4831–4835, 2010.
Titanium oxide nano particles addition led to temperature changing from 217 to 217.64 degree Celsius [7]. Zinc oxide bearing SAC had temperature of about 222.16
High Temperature Electronics
6
degree celsius when zinc was about 0.5% by weight [8]. From this it can be conclud-ed that there no major effect on melting temperature.
2.2.2 Wettability
It is the ability of …show more content…
They can grow upto several microns and have excellent electrical conductivity. Their growth can be re-tarded by adding 0.5% Zn, using reflowed tin or hot tin dip. Reflowed tin is a tech-nique that involves reheating a part above the melting temperature of tin after it has been electroplated with tin. Hot tin Dip is a process in which a part is dipped into a bath of molten tin above 450 F. This creates a thin layer at the interface of the base material & tin.
3.2 Voids
The voids can be removed by adding sintered silver foil that is already coated with chromium and gold. On reaction a uniform layer is formed between Ag/Sn & Sn/Au.
3.3 Reduction in Melting Point
Further reduction in melting point can be made by adding more of the rare earth ele-ments into Sn-Ag-Cu solder.
3.4 Calculation of melting Temperature
(Given)
High Temperature Electronics
10
3.5 State of the Art
The trend is shifting towards lead free solders with different base materials hypo eu-tectic Bi-Ag alloys are preferred based on liquidus temperature in comparison to PbSn solders. Zn-Al eutectic systems alloyed with Mg, Ge ,Ga ,Sn, Sb, Bi may serve interesting topics for …show more content…
Kanlayasiri, M. Mongkolwongrojn, and T. Ariga, “Influence of indium addition on characteristics of Sn-0.3Ag-0.7Cu solder alloy,” Journal of Alloys & Compounds, vol. 485, no. 1-2, pp. 225–230, 2009.
[7] L.W. Lin, J.M. Song, Y. S. Lai, Y. T. Chiu,N.C.Lee, and J. Y. Uan, “Alloying modification of Sn-Ag-Cu solders by manganese and titanium,” Microelectronics Reliability, Vol.49,no.3, pp235-241,2009.
[8] A. Fawzy, S. A. Fayek, M. Sobhy, E. Nassr, M. M. Mousa, and G. Saad, “Tensil -Creep characteristics of Sn−3.5Ag−0.5Cu(SAC355) solder reinforced with nano-metric ZnO Particles”, Materials Science and Engineering A, vol. 603, pp. 1-10, 2014.
High Temperature Electronics
12
[9] C. M. T. Law, C. M. L. Wu, D. Q. Yu, L. Wang, and J. K. L. Lai, “Microstructure, Solderability & growth of intermetallic compounds of Sn-Ag-Cu-RE lead-free solder alloys”, Journal of Electronic Materials, vol. 35, no. 1, pp. 89–93, 2006.
[10] L. Zhang, X. Y. Fan, Y. H. Guo, and C. W. He, “Properties enhancement of SnAgCu solders containing rare earth element Yb”, Materials & Design, Vol. 57, pp. 646–651, 2014.
[11] L. C. Tsao, S. Y. Chang, C. I. Lee, W. H. Sun, and C. H. Huang, “Effects of nano Al2O3 additions on microstructure development and hardness of Sn3.5Ag0.5Cu solder,” Materials and Design, vol. 31, no. 10, pp. 4831–4835, 2010.