Effect of bump height on the strain variation during the thermal cycling test of ACA flip-chip joints

Flip-chip joining using anisotropically conductive adhesive (ACA) has becom e a very attractive technique for electronics packaging. Many factors can i nfluence the reliability of the ACA flip-chip joint. Bump height, is one of these factors. In this work, the strain development during the thermal cyc ling test of flip-chip joining with different bump heights was studied, The effect of bump height is significant in the interface between the bumps an d the pads. Bigger volume area of high strain is found for higher bump in t he interface between the bumps and the pads. Our calculations show that the re is practically no effect of the bump height on the strain variation in t he bumps and in the pads.