Thermosyphon-Cooled Three-Dimensional Stacked Heat Sources

This article presents an experimental investigation of two-phase passive liquid cooling, using a miniature-thermosyphon, for the simulated three-dimensional stacked integrated chips (3D-SICs). An evaporator consisting of three heaters separated with two micro-gaps of height 0.178 mm serves as a core component of the miniature-thermosyphon system. The thermosyphon’s cooling performance has been evaluated under multiple parametric conditions, including evaporator tilt angle, vertical separation between the condenser and the evaporator, and inlet-chilled water temperature of the condenser in the auxiliary loop. Boiling regimes at evaporator outlets are presented. All the investigated characteristics except the tilt angle have notable impacts on the cooling performance of each layer of the simulated 3D-SICs. Nonuniform cooling performance between the simulated 3D-SICs layers and within each layer has been observed. This nonuniform cooling performance could require the preferred placement of 3D-SICs with heterogeneous chips in data center cabinets.