本研究主要討論無鉛銲料與(Bi,Sb)2Te3基材的界面反應和擴散阻礙層無電鍍鎳磷於銲料與(Bi,Sb)2Te3基材兩者中間的阻擋效果。第一部分為液態銲料與(Bi,Sb)2Te3基材的界面反應，不同銲料內的Sn與Te的反應生成SnTe。第二部分是無電鍍鎳磷與(Bi,Sb)2Te3基材熱處理後的反應，探討介金屬化合物的生成動力學和成分分析，而後再加上與SnAgCu銲料的迴銲反應並進行退火與電遷移作用下介金屬化合物的變化。
Sn-Ag、Sn-Cu、Sn-Ag-Cu與Sn-Ag-Ni內的Ag或Cu元素會與Te-rich相反應生成介金屬化合物， Ag5Te3和CuTe。無電鍍Ni-P/(Bi,Sb)2Te3系統，經過XRD與EPMA定量分析後得知兩者之間的介金屬化合物為Ni50(Bi,Sb,Te)50，此介金屬化合物生成所需的活化能為111kJ/mol。Ni-P/(Bi,Sb)2Te3與銲料Sn3Ag0.5Cu迴銲反應並於不同溫度退火後，介金屬化合物(Cu,Ni)6Sn5與NiTe皆有明顯成長，SnTe不存在於此系統中，Ni-P有效的妨礙Sn與Te彼此交互擴散。Sn3Ag0.5Cu/Ni-P/(Bi,Sb)2Te3/Ni-P/Sn3Ag0.5Cu在通入150℃與1×10^2A/cm2電流密度的作用下，因為熱電效應的影響使得陰極端較熱介金屬化合物較厚，Ni-P層有明顯的消耗，陽極端溫度較低介金屬化合物較薄。

The intermetallic compound SnTe rapidly formed at interfaces between p-type bismuth telluride (Bi,Sb)2Te3 thermoelectric materials and lead-free solders. The intermetallic compound influences the mechanical properties of the joints and the reliability of thermoelectric modules. Various lead-free solder alloys, Sn-3.5Ag, Sn-3Ag-0.5Cu, Sn-0.7Cu, and Sn-2.5Ag-2Ni were used to investigate the interfacial reactions. The results thus obtained that Ag and Cu preferentially diffused into the Te-rich phase in (Bi,Sb)2Te3, so layers of Ag-Te and Cu-Te compounds could not form as an effective diffusion barrier. Electroless nickel-phosphorus was plated at the interfaces to serve as a diffusion barrier, and the (Cu,Ni)6Sn5 compound formed instead of SnTe. Furthermore, the intermetallic compound Ni-Te formed between nickel-phosphorus and (Bi,Sb)2Te3 and also served as a diffusion barrier. A plot of thickness as a function of annealing time yielded the growth kinetics of the intermetallic compounds in thermoelectric material systems. The activation energy for the growth of Ni-Te intermetallic compound is 111kJ/mol.
Ni-P/(Bi,Sb)2Te3/Ni-P were used to investigate the behaviors under electromigration. Sn-3Ag-0.5Cu solder were reflowed and acted as the electrodes. The samples current stressed by a current density of 1×10^2A/cm2 at 150℃. The intermetallic compound formed between the solders, Ni-P layer and (Bi,Sb)2Te3. The major compounds at the interface are (Cu,Ni)6Sn5 and NiTe. The thicknesses of the intermetallic compound at the cathode were thicker than at the anode since thermoelectric effect induced a higher temperature at the cathode.

1.G.S. Nolas, J. Sharp, and H.J. Goldsmid. "Thermoelectrics : basic principles and new materials developments" (2001).
2.中央研究院週報，｢從溫室效應與地球暖化談到—高效率熱電材料的研發｣，第1169期，民國97年。
3.H. J. Fecht, M. X. Zhang, Y. A. Chang and J. H. Perepezko, “Metastable phase equilibria in the lead-tin alloy system: Part II. Thermodynamic Modelling”, Metall. Mater. Trans. A, 20, 795, (1989).
4.K. N. Tu, A. M. Gusak, and M. Li, “Physics and materials challenges for lead-free solders”, J. Appl. Phys., 93, No.3, (2003).
5.C. N. Liao, C. H. Lee, and W. J. Chen, “Effect of Interfacial Compound Formation on Contact Resistivity of Soldered Junctions Between Bismuth Telluride-Based Thermoelements and Copper”, Electrochem. Solid-State Lett., 10(9) P23-P25, (2007).
6.張淑如，「鉛對人體的危害」，勞工安全衛生簡訊，第12期，民國84年。
7.S. W. Chen and C. N. Chiu, “Unusual cruciform pattern interfacil reactions in Sn''Te couples” Scripta Mater. 56, 97–99, (2007)
8.C. N. Liao and Y. C. Huang, “Effect of Ag addition in Sn on growth of SnTe compound during reaction between molten solder and tellurium”, J. Mater. Res. 25, 391-395, (2010).
9.C. N. Liao and C. H. Lee, “Suppression of vigorous liquid Sn/Te reactions by Sn–Cu solder alloys”, J. Mater. Res., Vol. 23, No. 12, 3303, (2008).
10.C. N. Chiu, C. H. Wang and S. W. Chen, “Interfacial Reactions in the Sn-Bi/Te Couples”, J. Electron. Mater., Vol. 37, No. 1, 40, (2008).
11.V.Semenyuk, presented at the Thermoelectrics, 2001. Proceedings ICT 2001. XX International Conference, (2001).
12.Y. C. Lan, D. Z. Wang, G. Chen, and Z. F. Ren, “Diffusion of nickel and tin in p-type (Bi,Sb)2Te3 and n-type Bi2(Te,Se)3 thermoelectric materials”, Appl. Phys. Lett., 92, 101910, (2008).
13.O. D. Iyore et al, “Interface Characterization of Cobalt Contacts on Bismuth Selenium Telluride for Thermoelectric Devices”, Electrochem. Solid-State Lett., 12 (10) H395-H397, (2009).
14.A. D. Mah, and L. B. Pankratz, “Theoretical Metallurgy: XVI, Thermodynamic Properties of Nickel and its Inorganic Compounds”, vol. 668 (Ed.: B. o. M. United States Department of the Interior, Washington, 1976).
15.T. Kacsich, E. Kolawa, J. P. Fleurial, T. Caillat and M. A. Nicolet, J. Phys. D-Appl. Phys. 31 (19), 2406-2411, (1998).
16.K. N. Tu, T. Y. Lee, J. W. Jang, L. Li, D. R. Frear, K. Zeng and J. K. Kivilahti, “Wetting Reaction Versus Solid State Aging of Eutectic SnPb on Cu”, J. Appl. Phys., vol. 89, no. 9, 4843-4849, (2001).
17.Y. C. Chan et al,“Reliability Studies of BGA Solder Joints Effect of Ni–Sn Intermetallic Compound”, IEEE Trans. Adv. Packaging 24, 25–32, (2001).
18.P. L. LIU et al,“Thermal Stability of electroless-Nickel/Solder Interface: Part A. Interfacial Chemistry and Microstructure”, Metall. Mater. Trans. A 31A, 2857–2866, (2000).
19.W. D. Zhuang et al, “Diffusional Breakdown of Nickel Protective Coatings on Copper Substrate in Silver-Copper Eutectic Melts”, Metall. Mater. Trans. A 28A,969-976, (1999).
20.A. Brenner, and G.E. Riddell, U.S. Patent, 2, 532, 283, (Dec. 5, 1950).
21.W, J, Tomlinson and M. W. Carroll, “Substrate roughness, deposit thickness and the corrosion of electroless nickel coatings”, J. Mater. Sci., 25, 4972, (1990).
22.H. Wada, K. Takahashi and T. Nishizaka, “Electroless nickel plating to Bi-Te sintered alloy and its properties” J. Mater. Sci. 9(7), 810-812, (1990).
23.R. Paul, P. Buisson, and N. Joseph, “Catalytic Activity of Nickel Borides”, Ind. Eng. Chem, 44, 1006, (1952).
24.R. N. Duncan, “The metallurgical structure of electroless nickel deposits: effect of coating properties”, Plat. Surf. Finish 83(11), 65, (1996).
25.Z. Chen, M. He, and G. Qi, “Morphology and Kinetic Study of the Interfacial Reaction between the Sn-3.5Ag Solder and Electroless Ni-P Metallization”, J. Electron Mater., Vol. 33, No. 12, (2004).
26.J. W. Yoon, J. H. Park, C. C. Shur and S. B. Jung, “Characteristic evaluation of electroless nickel–phosphorus deposits with different phosphorus contents”, Microelectron. Eng. 84 (11) 2552-2557, (2007).
27.J. W. Yoon, and S. B. Jung, “Effect of isothermal aging on the interfacial reactions between Sn–0.4Cu solder and Cu substrate with or without ENIG plating layer”, Surf. Coating Tech., 200, 4440-4447, (2006).
28.P. L. Liu, Z. Xu, and J. K. Shang, “Thermal Stability of Electroless-Nickel Solder Interface Part A. Interfacial Chemistry and Microstructure”, Metall. Mater. Trans. A, 31A, 2857, (2000).
29.P. Sun, C. Andersson, X. Wei, Z. Cheng, Z. Lai, D. Shangguan, and J. Liu, “High Temperature Aging Study of Intermetallic Compound Formation of Sn-3.5Ag and Sn-4.0Ag-0.5Cu Solders on Electroless Ni (P) Metallization”, Electronic Components and Technology Conference, 1468, (2006).
30.K. N. Tu, “Recent advances on electromigration in very-large-scale-integration of interconnects”, J. Appl. Phys., 94 (9), (2003).
31.A. Kumara, M. Hea, Z. Chena, and P. S. Teob, “Effect of electromigration on interfacial reactions between Ni-P and Sn3.5%Ag solder”, Thin Solid Films 462–463, (2004).
32.http://quanzhou-melcor-huayu-thermoelectric.tradenote.net/product/304606-Thermoelectric-Module.html “TEC module”, (2006).
33.C. N. Liao, W. T. Chen, and C. H. Lee, “Polarity effect on interfacial reactions at soldered junctions of electrically stressed thermoelectric modules”, Appl. Phys. Lett., 97, 241906, (2010).
34.B. D. Cullity, and S. R. Stock, “Elements of x-ray diffraction”, (2001)
35.R. C. Sharma, and Y. A. Chang, “Sn-Te phase diagram” Bull. Alloy Phase Diagrams 7, 72, (1986).
36.T. B. Massalski, “Binary Alloy Phase Diagrams, Second Edition”, Vol. 2, The Materials Information Society, Materials Park, Ohio (1990).
37.L. Karakaya and W.T. Thompson, “The Ag-Te (Silver-Tellurium) System”, Journal of Phase Equilibria Vol. 12 No. 1, 56, (1991).
38.I. Barin, and G. Platzki: Thermochemical Data of Pure Substances (Wiley-VCH, New York, 1995), p. 1556.
39.P. Nash, and H. Choo, “Thermodynamic Calculation of Phase Equilibria in the Ti–Co and Ni–Sn Systems”, J. Mater. Sci., vol. 33, 4929-4936, (1998).
40.O. D. Iyore, T. H. Lee, R. P. Gupta, J. B. White, H. N. Alshareef, M. J. Kim, and B. E. Gnade, “Interface characterization of nickel contacts to bulk bismuth tellurium selenide”, Surf. Interface Anal., 41, 440, (2009).
41.H. Gan and K. N. Tu, “Polarity effect of electromigration on kinetics of intermetallic compound formation in Pb-free solder V-groove samples”, J. Appl. Phys., 97 063514, (2005).