This paper describes the effect of epoxy resin property on the reliability of semiconductor using a solder bump. First, thermal stress at the solder bump-Si chip interface was analyzed using a numerical method (two-dimensional elastic-plastic finite element analysis). Second, the reliability of semiconductor was evaluated by the energy release rate when the crack grew. Third, the effect of resin property on the deformation of substrate was analyzed. The numerical-calculation results showed that the Young's modulus of epoxy resin influenced significantly the value of this stress. As a result, reliability of semiconductor was able to be improved by icreasing Young's modulus value of the epoxy resin. Furthermore, the deformation of substrate decreased by reducing Young's modulus value of the epoxy resin.
