Copper base have been used for many semiconductor package to satisfy thermal radiation performance. However, copper base is easily deformed and curvature deformation increases during thermal cycle. In this research, the effect of temperature condition on copper base deformation during thermal cycle is evaluated quantitatively through experiments and finite element analyses (FEA). As a result, the more minimum temperature of heat cycle increases, the more curvature deformation decreases because plastic deformation of copper decrease. On the contrary, the more maximum temperature of heat cycle decreases, the more curvature deformation decreases because solder creep decreases. Therefore this phenomenon of curvature deformation is sensitively controlled by the temperature condition of thermal cycle. The results of elasto- plastic FEA that considers plasticity of copper and solder creep deformation agree well with the experimental result under various thermal cyclic conditions.
