Correlation of board and joint level test methods with strain dominant failure criteria for improving the resistance to pad cratering

Due to the advantages of joint level tests, such as low cost and flexibility, it is always desirable to predict the board level pad cratering strength by a joint level test. In order to achieve this objective, the correlation between the joint level and the board level tests must be fully understood. Nevertheless, a precise correlation between the two types of tests for pad cratering evaluation is yet to be defined. This study investigates the correlation methodology of critical failure factors between joint and board level tests on pad cratering failure mode. An intermediate critical failure factor is taken from joint level testing as a failure criterion for failure prediction in board level testing. From the results of the experimental study and finite element analysis (FEA), the critical failure factor correlation is established between the board level and the joint level test. Subsequently the obtained failure criterion is also verified by a board level experimental study. In consequence, this indirect correlation method has the capability to predict the board level pad cratering failure with various geometric parameters.