Title :
A viscoplastic constitutive model for 63Sn37Pb eutectic solders
Author :
Yi, Sung ; Luo, Guangxing ; Chian, Kerm Sin ; Chen, William T.
Author_Institution :
Sch. of Mech. & Production Eng., Nanyang Technol. Univ., Singapore
Abstract :
Solder joints serve both as electrical and mechanical connections in IC packages and the reliability of solder joints is one of most important issues in electronic packaging. In this study, a new constitutive model for eutectic solders (63Sn37Pb) is proposed. Grain sizes and phase sizes are considered as coarsening is one of the main reasons for solder joint failures. The model has been developed based on the combination of grain boundary sliding and matrix dislocation deformation mechanisms in order to describe the thermo-mechanical behavior of eutectic solders. Internal stress tensors are also introduced to describe the transient behavior during the tensile test and first stage creep. A series of tensile tests, creep and creep recovery tests were conducted over a temperature range from -10 to 100°C. Specimens with two different phase sizes were tested. Good agreements were obtained between the experimental results and the model
Keywords :
creep testing; eutectic alloys; grain size; integrated circuit interconnections; integrated circuit modelling; integrated circuit packaging; lead alloys; packaging; recovery-creep; slip; soldering; tensile testing; tin alloys; viscoplasticity; -10 to 100 C; IC packages; SnPb; SnPb eutectic solders; coarsening; constitutive model; creep recovery tests; creep tests; electrical connections; electronic packaging; eutectic solders; first stage creep; grain boundary sliding; grain sizes; internal stress tensors; matrix dislocation deformation mechanisms; mechanical connections; phase sizes; reliability; solder joint failures; solder joints; temperature range; tensile test; tensile tests; thermo-mechanical behavior; transient behavior; viscoplastic constitutive model; Creep; Deformable models; Electronics packaging; Grain boundaries; Grain size; Integrated circuit packaging; Internal stresses; Soldering; Testing; Thermomechanical processes;
Conference_Titel :
Electronic Materials and Packaging, 2000. (EMAP 2000). International Symposium on
Conference_Location :
Hong Kong
Print_ISBN :
0-7803-6654-9
DOI :
10.1109/EMAP.2000.904151
