在電子產品製造中，電子構裝為其中重要的一環。軟銲是電子構裝中最重要的連接技術。在軟銲過程中，熔融的銲料會與基材發生界面反應形成銲點。電子產品使用與銲點的可靠度息息相關，而銲點中的界面接著更影響其可靠度。由於異質材料之界面間存在化學勢梯度，造成界面處原子擴散及反應生成介金屬相，界面生成相的演變對於可靠度有很大的影響。Sn-Pb共晶銲料為昔日主要銲料，在禁鉛規定下，改採用無鉛銲料，此研究主要為探討無鉛銲料與基材間的界面反應。
在無鉛銲料的使用中，以Sn-Ag-Cu系統最為普遍，Ni為常見的障層材料，因此Sn-Ag-Cu/Ni界面反應為重要的研究議題，Ag並不參與界面反應相的生成，因此本研究以探討Sn-Cu/Ni液/固界面反應為主。以反應偶方式進行探討，在Sn-0.7wt%Cu/Ni界面處生成Cu6Sn5相，隨著反應，Cu6Sn5相發生剝落，並開始生成Ni3Sn4相，研究其整個反應流程。以不同的Cu、Ni組成比例銲料與Ni進行反應，探討Cu、Ni濃度對於界面反應之生成相微結構及反應流程的影響。當銲料中的Cu濃度增加時，會延遲反應流程的發生，而Ni濃度增加則加速反應過程的進行。另外亦進行銲料與Cu6Sn5相之界面反應，探討Cu6Sn5相轉變與Cu、Ni濃度之關係，當Cu濃度降低時，Cu6Sn5相會發生溶解，而Sn與Cu6Sn5相反應時，在界面處生成Ni3Sn4相。研究中也探討Sn-Cu/Cu6Sn5/Ni固相界面反應，分析Sn、Cu、Ni之擴散與相互關係。以熱力學、擴散與結構等基本知識，探討與分析上述液/固界面反應機制、固/固界面反應、微結構演變之機制。
電子產品最大的特點為電流通過，電流經過時，會造成電遷移效應，由於覆晶接合銲點縮小化，使得通過電流密度極遽提高，因此電遷移效應對接點造成嚴重破壞。本研究探討Sn/Cu、Sn/Ni界面在電遷移的作用下，因電流方向的不同而有差異，以Sn/Cu界面為例，以電流密度5000A/cm2對界面作用，當電子流由Sn端流至Cu端時，生成層狀Cu6Sn5與Cu3Sn相，當電子流由Cu至Sn時，會生成大區域的Cu6Sn5相，討論其擴散與反應機制，及電遷移效應與銲料微結構之關係。在Sn/Ni系統也有相似的現象，以不同的反應溫度與電流密度，探討電流通過對於界面反應之影響。另外也探討Sn-0.7wt%Cu/Ni、Sn-3wt%Cu/Ni界面，其電流作用與Cu、Ni、Sn擴散及生成相之關係。
目前已有許多研究以Co為UBM材料，因此進行Sn/Co界面反應之研究，發現固/固反應在界面生成CoSn3相，且為反應控制的線性成長，其臨界厚度高達87μm。在200oC的反應時，生成相為特殊的十字形結構，角落處之生成相成長時，因應力作用而導致生成相出現裂縫，此為固/固反應下首次發現的例子。在180oC下反應時，因成長較慢而產生的應力較小，角落處生成相轉而生成CoSn4相。設計各種不同形態之反應偶，探討十字形結構與應力之關係，當電流通過Sn/Co反應偶時，由於生成相成長為反應控制，電遷移效應對於生成相成長的擴散通量沒有影響，然而在電子流通過Co/Sn界面處之生成相成長快於另一端Sn/Co界面，本研究發現電流通過對Sn/Co反應偶時，派鐵耳效應造成兩側界面處出現溫度差異，電子流由Sn至Co之界面低於另一側，而使得界面生成相成長速率不同。Bi/Cu界面有顯著的熱電效應，利用紅外線熱像儀進行Bi/Cu/Bi、Sn/Co/Sn系統之溫度量測與確認。
Sn/Co之十字形生成相是以Co相位於Sn相之中，若將兩元素之區域對調，即Sn相位於Co相之中，探討其內凹直角處對於界面生成相成長的影響。事實上，電子產品的連結接點也包含各種不同幾何結構的界面，因此對於幾何結構對於界面反應的探討也有其研究的必要性。另外在熱電系統中，Bi、Te為重要的熱電材料，因此分別以Bi/Ni、Sn/Co、Sn/Te、Au/Sn等相關系統來探討內凹直角之界面反應。在成長過程中，其內凹直角端點必須固定不動，且角落附近的生成相因應力作用而成長受到抑制，亦由質量守恆的觀點分析角落處之生成相成長。另外以圓形反應偶來進行探討，圓形幾何結構造成的應力關係，對生成相成長亦有明顯的抑制，
本論文探討Sn-0.7wt%Cu/Ni之界面反應流程，在研究過程中，更探討銲料中的Cu、Ni濃度與Cu6Sn5相微結構與變化關係，此有助於完整瞭解電子無鉛銲點中的反應變化。電遷移效應對於覆晶接點影響相當大，本研究深入探討電流密度與銲料微結構對於界面反應之影響。Sn/Co系統的研究極具學術價值，在此系統不僅發現明顯的線性成長，亦觀察到十字形生成相，在電流的作用下，更證實派鐵耳效應對界面生成相的成長影響甚鉅。另外亦研究幾何結構對於界面反應的影響。本論文不僅在無鉛電子銲點與熱電材料上的應用議題上探討，更針對各個主題進行深入研究以豐富其學術價值。

Soldering is the most important joining technology in the electronic packaging industry. During the soldering processes, the molten solders wet and react with the substrates. Even though the soldering time is short, the substrates' interfacial reactions with the molten solders are much more intensive than those with the solid phases. The performance of the electronic products is close related to the interface reliability of solder joints. The diffusion of atoms and the formation of the reaction layers arise from the difference of the chemical potential existing at the interface between the different materials. The evolution of the reaction layer is crucial for the joint properties, and their information is fundamentally important for the proper reliability assessment of the electronic products.
Pb-Sn alloys are the most common solders. However, owing to the environmental and health hazardous concerns of Pb, various Pb-free solders have been developed to eliminate the usage of Pb. The Sn-0.7wt%Cu alloy and eutectic and near eutectic Sn-Ag-Cu alloys are highly recommended. Ni has relatively low reaction rates with most solders, and is usually used as the barrier layer material in the metallization substrate. With the emerging Sn-0.7wt%Cu solder, the Sn-Cu/Ni contact will be frequently encountered. This study investigates Sn-Cu/Ni interfacial reactions at 250oC with different Cu contents and reaction times. The morphologies and microstructures of the reaction phases are determined, the effects of Cu on the interfacial reactions are analyzed, and the reaction progressions of the interfacial reactions are proposed.
The passage of electric currents is the most important characteristic of the electronic products and it causes Joule heating and electromigration effects. Interfacial reactions are accelerated with elevated temperatures. Electromigration has polarity effects, and it might retard or enhance interfacial reactions. This study aims to examine the effects of electromigration on interfacial reactions of Sn/Cu, Sn/Ni, Sn-0.7wt%Cu/Ni and Sn-3wt%Cu/Ni joints, and the samples are prepared using a casting method. At the interfaces where electrons flow from the solder side to the substrate side, the results are similar to those without passage of electric currents. At the interfaces where electrons flow the substrate side to the solder side, large and non-planar reaction phase regions are formed.
Co and Co-alloys have been examined for their applicabilities as Pb-free solders and as under bump metallization materials. This study investigates the kinetics of Sn/Co solid/solid interfacial reaction. The reaction phase shows linear growth and the unique cruciform pattern which is observed for the first time in the solid/solid reaction. As electric currents pass through the Sn/Co interface, the difference of temperature due to significant Peltier effect affects the CoSn3 growth.

一、前言 1
二、文獻回顧 7
2-1 界面反應與相平衡之關係 7
2-2 界面反應動力學 9
2-3 電遷移效應 14
2-4 應力場效應 17
2-5 擴散機制 19
2-6 界面反應相之形態 23
2-7 界面反應相之形態演變 27
2-8 固化 31
2-9 銲料微結構之演變 33
2-10界面反應之實驗方法 35
2-11銲料系統相平衡與界面反應 37
2-11.1 Sn-Cu-Ni系統相平衡 37
2-11.2 Sn/Cu界面反應 39
2-11.3 Sn-Ag-Cu銲料/Cu界面之電遷移效應 40
2-11.4電遷移導致Cu大量溶入銲料 42
2-11.5 Sn-(Ag)-Cu/Ni之界面反應 43
2-11.6 Sn-Co二元系統相平衡 45
2-12 熱電效應 46
2-13 熱電元件 49
三、實驗方法 51
3-1 Sn-Cu/Ni之液/固界面反應 51
3-2 Sn-Cu/Cu6Sn5/Ni固/固界面反應 52
3-3 Sn/Cu電遷移實驗 53
3-4電鍍Ni 54
四、結果與討論 57
4-1 Sn-0.7wt%Cu/Ni液/固界面反應 57
4-2 Sn-Cu/Ni之液/固界面反應 83
4-3 Sn-Cu-Ni/Ni之液/固界面反應 109
4-4 Sn-Cu-(Ni)/(Cu,Ni)6Sn5之界面反應 131
4-5 Sn-Cu/Cu6Sn5/Ni之固/固界面反應 151
4-6電流效應對Sn/Cu界面反應之影響 169
4-7電流效應對Sn-(Cu)/Ni界面反應之影響 193
4-8 Sn/Co固/固界面反應 215
4-9電流效應對Sn/Co界面之影響 233
4-10 Sn/Co界面反應之十字形反應相 255
4-11幾何結構與界面反應 269
五、結論 293
參考文獻 299

1.J. S. Kilby, US patent 3138743, (1959).
2.K. Zeng and K. N. Tu, Materials Science and Engineering R. Vol. 38, pp. 55-105, (2002).
3.S.-W. Chen and Y.-E. Yen, Journal of Electronic Materials, Vol. 28, pp. 1203-1208, (1999).
4.Simon Green, Deborah Lea and Christopher Hunt, NPL Report CMMT(A)213, pp.1-10, (1999).
5.M. Abtew and G. Selvaduray, Materials Science and Engineering, Vol. 27, pp. 95-141, (2000).
6.C.-L. Tsao and S.-W. Chen, J. Materials Science, Vol. 30, pp. 5215-5222, (1995).
7.F. J. J. Van Loo, Progress in Solid State Chemistry, Vol. 20(1), pp. 47-99, (1990).
8.R. E. Reed-Hill and R. Abbaschian, “Physical Metallurgy Principles”, 3rd edition, PWS, Boston, pp. 365-367, (1994).
9.C. R. Kao, Materials Science and Engineering A, Vol.238, pp. 196-201, (1997).
10.C.-H. Wang, S.-W. Chen, C.-H. Chang, and J.-C. Wu, Metallurgical and Meterials Transactions A, Vol. 34, pp.199-209, (2003).
11.U. Gosele and K. N. Tu, Journal of Applied Physics, Vol. 53 (4), pp. 3252-3260, (1982).
12.V. I. Dybkov, “Reaction Diffusion and Solid State Chemical Kinetics”, The IPMS Publications, Kyiv, (2002).
13.K. N. Tu, Journal of Applied Physics, Vol. 94 (9), pp. 5451-5473, (2003).
14.C. M. Chen and S. W. Chen, Acta Materialia, Vol. 50, pp. 2461-2469, (2002).
15.C. M. Chen and S. W. Chen, Journal of Electric Materials, Vol. 28(7), Vol. 902-906, (1999).
16.C. M. Chen and S. W. Chen, Journal of Electric Materials, Vol. 29(10), Vol. 1222-1228, (2000).
17.C. M. Chen and S. W. Chen, Journal of Applied Physics, Vol. 90(3), pp. 1208-1214, (2001).
18.S. W. Chen, C. M. Chen, and W. C. Liu, Journal of Electric Materials, Vol. 27(11), Vol. 1193-1198, (1998).
19.H. T. Orchard and A. L. Greer, Applied Physics Letters, Vol. 86, pp. 231906/1-3, (2005).
20.C. Herring, Journal of Applied Physics, Vol. 21, pp. 437-445, (1950).
21.I. A. Blech, C. Herring, Applied Physcis Letters, Vol. 29, pp. 131-133, (1976).
22.B. F. Dyson, T. R. Anthony, and D. Turnbull, Journal of Applied Physics, Vol. 38, p. 3408, (1967).
23.F. J. J. van Loo, J. A. van Beek, G. F. Bastin, and R. Metselaar, in “Diffusion in Solids: Recent Developments”, edit by M. A. Dayananda and G. E. Murch, The Metallurgical Society, Inc., Warrendale, Pennsylvania (1985).
24.C. R. Kao and Y. A. Chang, Acta Metallurgical Materials, Vol. 41, pp. 3463-3472, (1993).
25.J. H. Maas, G. F. Bastin, and F. J. J. van Loo, and R. Metselaar, Journal of Applied Crystallography, Vol. 17, pp.103-110, (1984).
26.R. M. Cornell and U. Schwertmann, “The iron oxide, 2nd edition”, Wiley –VCH GmbH and Co. KGaA, Weinheim, (2004).
27.T. H. Chuang, S. Y. Chang, L. C. Tsao, W. P. Weng, and H. M. Wu, Journal of Electronic Materials, Vol. 32, pp.195-200 , (2003).
28.D. Ma, W. D. Wang, S. K. Lahiri, Journal of Applied Physics, Vol. 91(5), pp. 3312-3317, (2002).
29.S. W. Chen and C. N. Chiu, Scripta Materialia, Vol. 56(2), pp. 97-99, (2007).
30.E. Scheil, Zeitschrift Fur Metallkunde, Vol. 27, pp. 76-77, (1935).
31.J. Mackowiak and L.L. Shreir, Journal of the Less-Common Metals, Vol. 1, pp. 456-466, (1959).
32.F. Barbier and J. Blanc, Journal of Materials Research, Vol. 14, pp. 737-744, (1999).
33.張婉君碩士論文，中央大學，(2004)。
34.C.E. Ho, S. C. Yang, and C. R. Kao, Journal of Materials Science: Materials in Electronics, Vol. 18, pp. 155-174, (2006).
35.H. K. Kim and K. N. Tu, Physics Review B, Vol. 53(23), pp.16027-16034, (1996).
36.H. K. Kim and K. N. Tu, Applied Physics Letters, Vol. 67, pp. 2002-2004, (1995).
37.H. K. Kim, H. K. Liou, and K. N. Tu, Applied Physics Letters, Vol. 66(18), pp.2337-2339, (1995).
38.M. Schaefer, R. A. Fournelle, and J. Liang, Journal of Electronic Materials, Vol. 27(11), pp. 1167-1176, (1998).
39.A. M. Gusak and K. N. Tu, Physical Review B, Vol. 66, pp. 115403/1-14, (1996).
40.A. A. Liu, H. K. Kim and K. N. Tu, Journal of Applied Physics, Vol. 80, pp.2774-2780, (1996).
41.H. K. Kim, K. N. Tu and P. A. Totta, Applied Physics Letters, Vol. 68, pp. 2204-2206, (1996).
42.K. N. Tu, A. M. Gusak and M. Li, Journal of Applied Physics, Vol. 93(3), pp.1335-1353, (2003).
43.李守維碩士論文，清華大學，(2003)。
44.王朝弘碩士論文，清華大學，(2002)。
45.陳文泰碩士論文，中央大學，(2002).
46.C. E. Ho, R. Y. Tsai, Y. L. Lin, and C. R. Kao, Journal of Electronic Materials, vol. 31, pp.584-590, (2002).
47.K. W. Moon, W. J. Boettinger, U. R Kattner, C. A. Handwerker, and D. J. Lee, Journal of Electronic Materials, Vol. 30, pp.45-52, (2001).
48.L. Snugovsky , D. D. Perovic, and J. W. Rutter, Materials Science and Technology, Vol. 20, pp. 1403-1413, (2004).
49.A. U. Telang, T. R. Bieler, J. P. Lucas, K. N. Subramanian, L. P. Lehman, Y. Xing, and E. J. Cotts, Journal of Electronic Materials, Vol.33, pp.1412-1423, (2004).
50.T. Y. Lee, K. N. Tu, S. M. Kuo, and D. R. Frear, Journal of Applied Physics, Vol. 89(6), pp. 3189-3194, (2001).
51.J. W. Nah, K. W. Paik, J. O. Suh, and K. N. Tu, Journal of Applied Physics, Vol. 94(12), pp. 7560-7566, (2003).
52.C. H. Wang and S. W. Chen, Journal of Chinese Institute of Chemistry Engineers, Vol. 37(2), pp. 185-191, (2006).
53.S. W. Chen, S. K. Lin, and J. M. Jao, Materials Transaction, Vol. 45(3), pp. 661-665, (2004).
54.C. Y. Liu, C. Chen, C. N. Liao, K. N. Tu, Applied Physcis Letters, Vol. 75(1), pp. 58-60, (1999).
55.Q. T. Huynh, C. Y. Liu, C. Chen, K. N. Tu, Journal of Applied Physics, Vol. 89(8), pp. 4332-4335, (2001).
56.A. Paul dissertation, the kirkendall effect in the solid state diffusion.
57.V. I. Dybkov and O. V. Duchenko, Journal of Alloys and compounds, Vol. 234(2), pp. 295-300, (1996).
58.D. J. Chakrabarti, D. E. Laughlin, S.-W. Chen, and Y. A. Chang, “Phase Diagrams of Binary Nickel Alloys”,edited by P. Nash, ASM, Materials Park, pp. 85-95, (1991).
59.N. Saunders and A. P. Miodownik, Bulletin of Alloy Phase Diagrams, Vol. 11, No. 3, pp.278-287, (1990).
60.P. Nash and A. Nash, Bulletin of Phase Diagrams, Vol. 6, No. 4, pp.350-359, (1985).
61.C.-H. Lin, S.-W. Chen, and C.-H. Wang, Journal of Electronic Materials, Vol. 31(9), pp. 907-915, (2002).
62.C.-H. Wang and S.-W. Chen, Metallurgical and Materials Transactions A, Vol. 34A, pp. 2281-2287, (2003).
63.A. Hayashi, C. R. Kao, and Y. A. Chang, Scripta Materialia, Vol. 37(4), pp. 393-398, (1997).
64.J. Gorlich and G. Schmitz, and K. N. Tu, Applied Physics Letters, Vol. 86, pp. 053106/1-3, (2005).
65.F. Bartels and J. W. Morris, Jr. G. Dalke, and W. Gust, Journal of Electric Materials, Vol, 23(8), pp.787-790, (1994).
66.R. A. Gagliano and M. E. Fine, Journal of Electric Materials, Vol. 32(12), pp. 1441-1447, (2003).
67.L. H. Su, Y. W. Yen, C. C. Lin, and S. W. Chen, Metallurgical and Materials Transaction B, Vol. 28, pp. 927-934, (1997).
68.H. K. Kim and K. N. Tu, Physics Review B, Vol. 53(23), pp.16027-16034, (1996).
69.A. Paul, A. A. Kodentsov, and F. J. J. Van Loo, Z. Metallkd. Vol. 95(10), pp. 913-920, (2004).
70.K. N. Tu and R. D. Thompson, Acta Metallurgica, Vol. 30, pp. 947-952, (1982).
71.Z. Mei, A. J. Sunwoo, and J. W. Morris, Journal of Metallurgical Transactions A. Vol. 23A, pp. 857-864, (1992).
72.P. T. Vianco, J. A. Rejent, and P. F. Hlava, Journal of Electronic Materials, vol. 33(9), pp. 991-1004, (2004).
73.H. Gan and K. N. Tu, Journal of Applied Physics, Vol. 97, pp. 63514/1-10, (2005).
74.Y. C. Hu, Y. H. Lin, C. R. Kao, and K. N. Tu, Journal of Materials Research, Vol. 18(11), pp. 2544-2548, (2003).
75.Y. H. Lin, C. M. Tsai, Y. C. Hu, Y. L. Lin, and C. R. Kao, Journal of Electronic Materials, Vol. 34(1), pp. 27-33, (2005).
76.Y. H. Hsiao, Y. C. Chuang, and C. Y. Liu, Scripta Materialia, Vol. 54, pp. 661-664, (2006).
77.C. T. Lin, Y. C. Chuang, S. J. Wang, and C. Y. Liu, Applied Physics Letters, Vol. 89, pp. 101906/1-3, (2006).
78.C. Y. Liu, Lin Ke, Y. C. Chuang, and S. J. Wang, Journal of Applied Physics, Vol. 100, pp.83702/1-8, (2006).
79.H.-F. Hsu and S.-W. Chen, Acta Materialia, Vol. 52, pp. 2541-2547, (2004).
80.J. W. Yoon, S. W. Kim, and S. B. Jung, Journal of Alloys and Compounds, Vol. 392, pp. 247-252, (2005).
81.S. J. Wang, H. J. Kao, and C. Y. Liu, Journal of Electric Materials, Vol. 33(10), pp.1130-1136, (2004).
82.C. E. Ho, Y. L. Lin, and C. R. Kao, Chemistry of Materials, Vol. 14(3), pp. 949-951, (2002).
83.W. T. Chen, C. E. Ho, and C. R. Kao, Journal of Materials Research, Vol. 17(2), pp. 263-266, (2002).
84.D. Q. Yu, C. M. L. Wu, D. P. He, N. Zhao, L. Wang, and J. K. L. Lai, Journal of Materials Research, Vol. 20(8), pp. 2205-2212, (2005).
85.S. C. Hsu, S. J. Wang, and C. Y. Liu, Journal of Electric Materials, Vol. 32(11), pp. 1214-1221, (2003).
86.T. Laurila, V. Vuorien, J. K. Kivilahti, Materials Science and Engineering R, Vol. 49, pp. 1-60, (2005).
87.J. W. Yoon, S. K. Kim, and S. B. Jung, Journal of Alloys and Compounds, Vol. 391, pp. 82-89, (2005).
88.W. C. Luo, C. E. Ho, J. Y. Tsai, Y. L. Lin, and C. R. Kao, Materials Science and Engineering A, Vol. 396, pp. 385-391, (2005).
89.M. O. Alam, Y. C. Chan, and K. N. Tu, J. K. Kivilahti, Chemistry of Materials, Vol. 17(9), pp. 2223-2226, (2005).
90.G. P. Vassilev, K. I. Lilova and J. C. Gachon, Intermetallics, Vol. 15, pp. 1156-1162, (2007).
91.A. Lang and W. Jeitschko, Z. Metallkd. Vol. 87, pp. 759-764, (1996).
92.CRC Handbook of Thermoelectrics, edited by D. M. Rowe, CRC Press, Boca Raton, FL, (1995).
93.H. Odahara, O. Yamashita, K. Satou and S. Tomiyoshi, Journal of Applied Physics, Vol. 97, pp. 103722/1-5, (2005).
94.R. A. Horne, Journal of Applied Physics, Vol. 30(3), pp. 393-397,(1959).
95.R. Labie, E. Beyne and P. Ratchev, Proceeding of the 53rd ECTC Conference, 1230-1234, (2003).
96.K. N. Tu and R. D. Thompson, Acta Metallurgica. Vol. 30, pp. 947-952, (1982).
97.C.-D. Lien, M.-A. Nicolet and S. S. Lau, Thin Solid Films, Vol. 14, pp. 363-72, (1986)