Study on enhancing the heat dissipation in flip chip electronic packages

In the first part of this paper the approaches to enhance the heat transfer efficiency in the flip chip packages are reviewed. Thereafter, the effect of defects on heat transfer and thence the induced thermal stress in flip chip packages are evaluated by finite element method. A two-dimensional 4-node couple-field-element analysis is employed to account the thermal-mechanical interactions. It is interesting to note that the presence of delamination between the underfill resin and other package components substantially hindered the heat dissipation away from the active die surface. It is also noted that the length of delamination influences the overall stress distribution of the package and therefore the initial failure site within the package.