This study demonstrates the application of three-point and four-point bending tests for evaluating the reliability of chip scale packages under curvature loads. A three-point bend test is conducted on 0.5-mm-pitch chip-scale packages (CSPs) mounted on FR4 (Flame Retardant) substrates. This test is simulated by using the finite element method and the results are calibrated experimentally to formulate a reliability model. A three-point bend scheme is an ideal choice for generating reliability models because multiple packages can be tested under multiple loads in a single test. This reliability model can be used to predict the durability of the packages in the real product under any printed wiring board (PWB) curvature loading conditions. A four-point bending simulation is also demonstrated on the test substrate. Four-point bending test is an ideal method for testing a larger sample size of packages under a particular predefined stress level. This paper describes the bending simulation and testing on packages in a generic sense. Due to the confidentiality of the test results, the package constructional details, material properties, and the actual test data have not been presented here.

Darveaux, R., and Banerji, K., 1992, “
Constitutive Relations for Tin Based Solder Joints,” Electronic Components and Technology Conference, San Diego, California, May 18–20, pp. 538–551. 15, pp. 1013–1024.
Darveaux, R. 2000, “Effect of Simulation Methodology on Solder Joint Crack Growth Correlation,” Electronic Components and Technology Conference, Las Vegas, Nevada, May 21–24, pp. 1048–1058.
Darveaux, R., 1997, “Solder Joint Fatigue Life Model,” Proceedings TMS.
Shetty, S., Dasgupta, A., Halkola, V., Lehtinen, V., Reinikainen, T., 2000, “Bending Fatigue Of Chip Scale Package Interconnects,” ASME International Mechanical Engineering Congress and Exposition, Orlando, Florida, Nov. 5–10.
Shetty, S., 2000, “Effect Of Cyclic Bending On Chip Scale Package Assemblies,” M.S. thesis, Dept. of Mechanical Engineering, University of Maryland, College Park.
, “
Three-Dimensional Effects of Solder Joints in Micro-Scale BGA Assembly
ASME J. Electron. Packag.
, pp.
You do not currently have access to this content.