Package with integrated wick layer and method for heat removal

Abstract

A package for a die includes a porous wick layer disposed between the die and a substrate. A sealed chamber between the die and substrate includes a phase-change fluid to transfer heat from a substrate side of the die to a heat spreader. Interconnects coupling bonding pads of the die to the substrate may pass through the chamber and through vias in the wick layer. In embodiments, the wick layer may have a coefficient of thermal expansion (CTE) matching a CTE of the die of the heat spreader. Heat generated by the die may evaporate the fluid in a die region and the evaporated fluid may condense in a heat spreader region. The wick layer returns the condensed fluid from the heat spreader region to the die region to complete the cycle. The fluid may be non-corrosive with respect to the interconnects and may be an electrical insulator. In embodiments, the wick layer in the heat spreader region may be disposed on the heat spreader in a pattern to efficiently draw the condensed fluid to the die region. In other embodiments, the wick layer may comprise materials of different pore size and porosity to efficiently draw the condensed fluid to the die region.