Thermal cycling of lead‐free Sn‐3.8Ag‐0.7Cu 388PBGA packages

Emerald - 2009
C.Andersson1, B.Vandevelde2, C.Noritake2, P.Sun3, P.E.Tegehall4, D.R.Andersson4, G.Wetter4, J.Liu3
1Department of Microtechnology and Nanoscience, Chalmers University of Technology Sino‐Swedish Microsystem Integration Technology (SMIT) Center, Gothenburg, Sweden
2IMEC, Leuven, Belgium
3Department of Microtechnology and Nanoscience, Chalmers University of Technology Sino‐Swedish Microsystem Integration Technology (SMIT) Center, Gothenburg, Sweden Key State Lab for New Displays and System Applications and SMIT Center, Shanghai University, Shanghai, People's Republic of China
4IVF Industrial Research and Development Corporation, Mölndal, Sweden

Tóm tắt

PurposeThe purpose of this paper is to assess the effect of different temperature cycling profiles on the reliability of lead‐free 388 plastic ball grid array (PBGA) packages and to deeply understand crack initiation and propagation.Design/methodology/approachTemperature cycling of Sn‐3.8Ag‐0.7Cu PBGA packages was carried out at two temperature profiles, the first ranging between −55°C and 100°C (TC1) and the second between 0°C and 100°C (TC2). Crack initiation and propagation was analyzed periodically and totally 7,000 cycles were run for TC1 and 14,500 for TC2. Finite element modeling (FEM), for the analysis of strain and stress, was used to corroborate the experimental results.FindingsThe paper finds that TC1 had a characteristic life of 5,415 cycles and TC2 of 14,094 cycles, resulting in an acceleration factor of 2.6 between both profiles. Cracks were first visible for TC1, after 2,500 cycles, and only after 4,000 cycles for TC2. The crack propagation rate was faster for TC1 compared to TC2, and faster at the package side compared to the substrate side. The difference in crack propagation rate between the package side and substrate side was much larger for TC1 compared to TC2. Cracks developed first at the package side, and were also larger compared to the substrate side. The Cu tracks on the substrate side affected the crack propagation sites and behaved as SMD. All cracks propagated through the solder and crack propagation was mainly intergranular. Crack propagation was very random and did not follow the distance to neutral point (DNP) theory. FEM corroborated the experimental results, showing both the same critical location of highest creep strain and the independence of DNP.Originality/valueSuch extensive work on the reliability assessment of Pb‐free 388 PBGA packages has never been performed. This work also corroborates the results from other studies showing the difference in behavior between Pb‐free and Pb‐containing alloys.

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Tài liệu tham khảo

Andersson, C., Andersson, D.R., Tegehall, P.‐E. and Liu, J. (2004), “Effect of different temperature cycle profiles on the crack propagation and microstructural evolution of Sn‐3.8Ag‐0.7Cu solder joints of different electronic components”, Proceeding of the 5th International Conference on Thermal and Mechanical Simulation and Experiments in Microelectronics and Microsystems – EuroSimE 2004, Belgium, pp. 455‐64.

Arulvanan, P., Zhong, Z. and Shi, X. (2006), “Effect of process conditions on reliability, microstructure evolution and failure modes of SnAgCu solder joints”, Microelectronics Reliability, Vol. 46, pp. 432‐9.

Chang, T.C., Wang, J.W., Wang, M.C. and Hon, M.H. (2006), “Solderability of Sn‐9Zn‐0.5Ag‐1In lead‐free solder on Cu substrate Part 1. Thermal properties, microstructure, corrosion and oxidation resistance”, Journal of Alloys and Compounds, Vol. 422, pp. 239‐43.

Chen, H.T., Wang, C.Q. and Li, M.Y. (2006), “Numerical and experimental analysis of the Sn3.5Ag0.75Cu solder joint reliability under thermal cycling”, Microelectronics Reliability, Vol. 46, pp. 1348‐56.

Chung, K., Mustapha, C., Hua, F. and Aspandiar, R. (2002), “An assessment of lead free solder (Sn3.7Ag0.8Cu) wettability”, Proceedings of the 4th Electronics Packaging Technology Conference, EPTC, Singapore, pp. 1‐5.

Conway, P.P. (1995), “Solderability testing of alternate component termination materials with lead free solder alloys”, Proceedings of the IEEE/CPMT International Electronics Manufacturing Technology Symposium, pp. 245‐51.

Frear, D.R., Jones, W.B. and Kinsman, K.R. (1990), Solder Mechanics, A State of the Art Assessment, TMS, Warrendale, PA.

Frear, D.R., Morgan, H., Burchett, S. and Lau, L. (1994), The Mechanics of Solder Alloy Interconnects, Van Norstrand Reinhold, New York, NY.

Fulong, Z., Honghai, Z., Rongfeng, G. and Sheng, L. (2007), “The effect of temperature and strain rate on the tensile properties of a Sn99.3Cu0.7 (Ni) lead‐free solder alloy”, Microelectronic Engineering, Vol. 84, pp. 144‐50.

Huang, H.Z., Wei, X.Q., Zhou, L., Liu, X.D. and Guo, G.L. (2006), “Effects of Zn concentration on wettability of Sn‐Zn alloy on Cu and on the interfacial microstructure between Sn‐Zn alloy and Cu”, Acta Metallurgica Sinica (Eng. Lett.), Vol. 19 No. 4, pp. 251‐7.

IPC‐7095A (2000), Design and Assembly Process Implementation for BGAs, Section 6.2.3, IPC, Bannockburn.

IPC‐SM‐785 (1992), Guideline for Accelerated Reliability Testing of Surface Mount Attachments, Section 7.8. Failure criteria for solder joint failure tests, IPC, Bannockburn.

Lau, J.H. (1991), Solder Joint Reliability – Theory and Applications, Van Norstrand Reinhold, New York, NY.

Laurila, T., Mattila, T., Vuorinen, V., Karppinen, K., Li, J., Sippola, M. and Kivilahti, J.K. (2007), “Evolution of microstructure and failure mechanism of lead‐free solder interconnections in power cycling and thermal shock tests”, Microelectronics Reliability, Vol. 47 No. 7, pp. 1135‐44.

Lee, J.G. and Subramaniam, K.N. (2007), “Effect of TMF heating rates on damage accumulation and resultant mechanical behavior of Sn‐Ag based solder joints”, Microelectronics Reliability, Vol. 47 No. 1, pp. 118‐31.

Levis, K.‐M. and Mawer, A. (2000), “Assembly and solder joint reliability of plastic ball grid array with lead‐free versus lead‐tin interconnect”, Proceedings of the IEEE, 2000 Electronic Components and Technology Conference, Orlando, FL, pp. 1198‐204.

Lu, H.Y., Balkan, H. and Ng, K.Y.S. (2006), “Microstructure evolution of the Sn‐Ag‐y%Cu interconnect”, Microelectronics Reliability, Vol. 46, pp. 1058‐70.

Masazumi, A., Masako, W., Masaki, O., Kikuo, K. and Toshikazu, S. (2002), “Mechanical characterization of Sn‐Ag‐based lead free solders”, Microelectronics Reliability, Vol. 42, pp. 951‐66.

Matin, M.A., Vellinga, W.P. and Geers, M.G.D. (2007), “Thermomechanical fatigue damage evolution in SAC solder joints”, Materials Science and Engineering, Vol. 445/446, pp. 73‐85.

Mavoori, H. and Chin, J. (1995), “Reliability, lifetime prediction and accelerated testing of prospective alternatives to lead‐base solder”, Proceedings of the 45th Conference on Electronic Components and Technology, Las Vegas, NV, USA, pp. 990‐8.

Meilunas, M., Primavera, A. and Dunford, S.O. (2002), “Reliability and failure analysis of lead‐free solder joints”, IPC Annual Meeting, pp. S04‐S08.

Melton, C. (1993), “Reflow evaluation of lead free solder”, 43rd Proceedings on Electronic Components and Technology Conference, pp. 1008‐11.

Moy, W.H. and Shen, Y.‐L. (2007), “On the failure path in shear‐tested solder joints”, Microelectronics Reliability, Vol. 47 No. 8, pp. 1300‐5.

Nurmi, S., Sundelin, J., Ristolainen, E. and Lepistö, T. (2004), “The effect of solder paste composition on the reliability of SnAgCu joints”, Microelectronics Reliability, Vol. 44, pp. 485‐94.

Qi, Y., Lam, R., Ghorbani, H.R., Snugovsky, P. and Spelt, J.K. (2006), “Temperature profile effects in accelerated thermal cycling of SnPb and Pb‐free solder joints”, Microelectronics Reliability, Vol. 46, pp. 574‐88.

Suganuma, K. (2001), “Advances in lead‐free electronics soldering”, Current Opinion in Solid State & Materials Science, Vol. 5 No. 1, pp. 55‐64.

Sun, P., Andersson, C., Cheng, X.W.Z., Shangguan, D. and Liu, J. (2006), “Intermetallic compound formation in Sn‐Co‐Cu, Sn‐Ag‐Cu and eutectic Sn‐Cu solder joints on electroless Ni(P) immersion Au surface finish after reflow soldering”, Materials Science and Engineering, B, Vol. 135, pp. 134‐40.

Sundelin, J.J., Nurmi, S.T., Lepistö, T.K. and Ristolainen, E.O. (2006), “Mechanical and microstructural properties of SnAgCu solder joints”, Materials Science and Engineering, A, Vol. 420, pp. 55‐62.

Tegehall, P.‐E. and Dunn, B.D. (2001), “Assessment of the reliability of solder joints of ball and column grid array packages for space applications”, ESA STM‐266, ESA Publications Division, Noodwijh.

Vandevelde, B., Gonzalez, M., Limaye, P., Ratchev, P. and Eric, B.E. (2007), “Thermal cycling reliability of SnAgCu and SnPb solder joints: a comparison for several IC‐packages”, Microelectronics Reliability, Vol. 47 Nos 2/3, pp. 259‐65.

Zeng, K. and Tu, K.N. (2002), “Six cases of reliability study of Pb‐free solder joints in electronic packaging technology”, Materials Science and Engineering: R: Reports, Vol. 38, pp. 55‐105.

Zhang, Q., Dasgupta, A. and Haswell, P. (2005), “Isothermal mechanical durability of three selected Pb‐free solders: Sn‐3.9Ag0.6Cu, Sn‐3.5Ag, and Sn0.7Cu”, Journal of Electronic Packaging, Vol. 127, pp. 512‐22.

Zhu, F., Zhang, H., Guan, R. and Liu, S. (2007), “Effects of temperature and strain rate on mechanical property of Sn96.5Ag3Cu0.5”, Journal of Alloys and Compounds, Vol. 438 Nos 1/2, pp. 100‐5.