Coupled thermal-mechanical simulation methodology to estimate BGA reliability of 2.5D Packages

The current paper describes finite element method based simulations to assess 2.5D package BGA solder joint reliability in accelerated thermal cycling and field-like cycling conditions. In addition to this, thermal cycling reliability test procedure and analysis for a large body, low CTE organic laminate 2.5D package with reticle stitched interposer, reticle size logic die, 2 HBMs is described. Two different configurations, one with a heat sink and one without heat sink are tested to assess the effect of heat sink solution on BGA reliability. Simulation results are compared to test results in terms of critical BGA location and number of cycles to failure. After validating the model, the coupled thermal-mechanical simulation technique is used to analyze BGA lifetime in different field cycling conditions.