1103 Distribution of Local Deformation of Thinned Si Chips Depending on Micro Bump Layout
Details
When the thickness of a Si chip is thinned to less than 100 μm, large local thermal deformation of the thinned Si chip appears easily due to the CTE mismatch between bump and underfill materials in an area-arrayed flip chip bonding structure. And the amplitude of this local deformation is strongly depending on the structural and material factors of flip chip bonding structures. The authors have measured the change of the local deformation of a Si chip assembled by area-arrayed flip chip technology. It was confirmed that the local deformation changes from 0.1 μm to 2.5 μm depending on the bump pitch and the mechanical properties of underfill material.
