3D IC With Embedded Microfluidic Cooling: Technology, Thermal Performance, and Electrical Implications

In this paper, a novel thermal testbed with an embedded micropin-fin heat sink is designed and fabricated. The micropin-fin array has a nominal height of 200 μm and a diameter of 90 μm. Single phase and two phase thermal testing of the micropin-fin array heat sink are performed using deionized (D.I.) water as the coolant below atmospheric pressure. The measured pressure drop is as high as 100 kPa with a mass flux of 1637 kg/m²s at a heat flux of 400 W/cm² in a two-phase regime. The heat transfer coefficient and the vapor quality are calculated and reported. The impact of microfluidic cooling on the electrical performance of the 3D interconnects is also analyzed. The high aspect ratio through silicon vias (TSVs) used in the electrical analysis have a nominal diameter of 10 μm.