A heat sink and method for using the same for use in cooling an integrated circuit (IC) chip is provided herein. The heat sink includes a manifold block, a liquid-filled cooling system, and a compliant foil affixed to the manifold block and backed by a liquid in the closed loop cooling system. The pressure provided by the liquid behind the foil causes the foil to bow, and to conform to non-planarities in the surface of the IC chip, thus reducing air gaps and increasing thermal coupling between the IC chip and the heat sink.