Published online by Cambridge University Press: 10 August 2011
The impact of microbump geometry, layout and underfill material properties on the device performance as well as the structural reliability is examined. Numerical simulations reveal that the magnitude of n-type carrier mobility change correlates with the increase in the underfill CTE and modulus as well as microbump pitch and height, but the decrease in the microbump radius. The crack driving force dependence on material property and geometry differs from that of mobility change. While the driving force is crack location dependent, the greater crack driving force corresponds to larger underfill CTE and bump radius, but smaller underfill modulus and microbump pitch.