Abstract
With the increasing application of flip-chip technology in the microelectronics industry, the adhesion strength of interfaces in flip-chip microelectronic structures has become an important issue for manufacturing and operation. In this paper we present an experimental investigation of the adhesive strength of underfill material to solder mask coated FR-4 substrate under thermal cycling. The effects of the number of thermal cycles on interfacial strength were investigated by using the button shear test. The relationship between interfacial strength and the thickness of solder mask was also examined. Furthermore, the morphologies of fracture surfaces of the test specimens were analyzed by scanning electron microscopy. The results of this study show that the interfacial strength of the underfill/solder mask/substrate joint was significantly reduced by thermal fatigue. Finally, the degradation behavior and possible mechanisms were then determined on the basis of these observations.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
Suhir, E., “The Future of Microelectronics and Photonics and the Role of Mechanics and Materials,”ASME, Journal of Electronic Packaging,120,1–11 (1998).
Chong, T.O., Ong, S.H. and Yew, T.G., “Low Cost Flip Chip Package Design Concepts for High Density I/O,” IEEE Electronic Components and Technology Conference, Orlando, FL, USA, 1140–1143 (2001).
Tong, Q., Ma, B., Xiao, A., Savoca, A., Luo, S., and Wong, C.P., “Fundamental Adhesion Issues for Advanced Flip Chip Packages,” IEEE Electronic Components and Technology Conference, 1373–1379 (2002).
Bressers, H., Beris, P., Cacrs, J., and Wondegem, J., “Influence of Chemistry and Processing of Flip Chip Underfills on Reliability,” Proceedings of the 2nd International Conference on Adhesive Joining Coating Technology and Electronic Manufacturing, Sweden (1996).
Ume, I.C., Martin, C., andGatro, J.T., “Finite Element Analysis of PWB Warpage Due to the Solder Masking Process,”IEEE Transactions on Components, Packaging, and Manufacturing Technology, Part A,20,295–306 (1997).
Zhu, H., Guo, Y., Li, W.Y., Tseng, A.A., and Martin, B., “Micromechanical Characterization of Solder Mask Materials,” IEEE Electronics Packaging Technology Conference, Singapore, 148–153 (2000).
Leung, S.Y.Y., Lam, D.C.C., and Wong, C.P., “Experimental Investigation of Time Dependent Degradation of Coupling Agent Bonded Interfaces,” IEEE Electronic Components and Technology Conference, Orlando, FL, USA, 1333–1337 (2001).
Royce, B.H., “Differential Thermal Expansion in Microelectronic Systems,” IEEE Complete manuscript reviewed by I-THERM Program Committee, Los Angeles, CA, USA, 171–180 (1988).
Kinloch, A.J., “Adhesion and Adhesives-Science and Technology,”Chapman and Hall, London (1990).
Fan, L., Moon, K.S., andWong, C.P., “Adhesion Study on Underfill Encapsulant Affected by Flip Chip Assembly Variables,”IEEE International Symposium on Advanced Packaging Materials, Braselton, GA, USA, 213–217 (2001).
Ferguson, T.P., and Qu, J., “Moisture Absorption in No-Flow Underfill Materials and Its Effect on Interfacial Adhesion to Solder Mask Coated FR4 Printed Wiring Board,” IEEE International Symposium on Advanced Packaging Materials, Braselton, GA, USA, 327–332 (2001).
Stone, B., Czarnowski, J.M., and Guajardo, J.R., “High Performance Flip Chip PBGA Development,” IEEE Electronic Components and Technology Conference, Orlando, FL, USA, 997–1002 (2001).
Shi, X.Q., Wang, Z.P., Pang, H.J., andZhang, X.R., “Investigation of Effect of Temperature and Strain Rate on Mechanical Properties of Underfill Material by Use of Microtensile Specimens,”Paymer Testing 21 (6),725–733 (2002).
Pyland, J., Pucha, R.V., andSitaraman, S.K., “Thermalmechanical Reliability of Underfilled BGA Packages,”IEEE Transactions on Electronics Packaging Manufacturing,25, (2),100–106 (2002).
Schubert, A., Dudek, R., Michel, B., and Reichl, H., “Materials Mechanics and Mechanical Reliability of Flip Chip Assemblies on Organic Substrates,” IEEE International Symposium on Advanced Materials Packaging, Braselton, GA, USA, 106–109 (1997).
Cheng, Z., Xu, B., Zhang, Q., Cai, X., Huang, W., and Xie, X., “Underfill Delamination Analysis of Flip Chip on Low-Cost Board,” IEEE International Symposium on Electronic Materials and Packaging, Jeju Island, South Korea, 280–285 (2001).
Cheng, Z., Chen, L., Wang, G.Z., Xie, X.M., and Zhang, Q., “The Effects of Underfill and Its Material Models on Thermomechanical Behaviors of Flip Chip Package,” IEEE International Symposium on Electronic Materials and Packaging, Hong Kong, China, 232–239 (2000).
Luo, S. and Wong, C.P., “Environmental Influence on Adhesion of Underfill with Passivation Materials,” IEEE International Symposium on Advanced Materials Packaging, Braselton, GA, USA, 305–311 (2001).
JESD22-A104-B, “Temperature Cycling,” JEDEC Solid State Technology Association (July 2000).
Szeto, W.K., Xie, M.Y., Kim, J.K., Yuen, M.F., Tong, P., and Yi, S., “Interface Failure Criterion of Button Shear Test as a Means of Interface Adhesion Measurement in Plastic Packages,” IEEE International Symposium on Electronic Materials and Packaging, Hong Kong, China, 263–268 (2000).
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Chien, C.H., Chen, Y.C., Hsieh, C.C. et al. Thermomechanical behavior of underfill/solder mask/substrate interface under thermal cycling. Experimental Mechanics 44, 214–220 (2004). https://doi.org/10.1007/BF02428181
Received:
Accepted:
Issue Date:
DOI: https://doi.org/10.1007/BF02428181