Flip chip package unit and associated packaging method

Abstract

A flip chip package unit and associated packaging method. The flip chip package unit may include an integrated circuit (“IC”) die having a plurality of metal pillars formed on its first surface and attached to a rewiring substrate with the first surface of the IC die facing to the rewiring substrate, an under-fill material filling gaps between the first surface of the IC die and the rewiring substrate, and a back protective film attached to a second surface of the IC die. The back protective film may have good UV sensitivity to change from non-solid to solid after UV irradiation while maintaining its viscosity with the IC die not reduced after UV irradiation. The back protective film may be uneasy to deform and to peel off from the IC die and can provide physical protection and effective heat dissipation path to the IC die.

Dependencies are inferred from the claim text.