Three Dimensional Integrated Circuit With Embedded Microfluidic Cooling: Technology, Thermal Performance, and Electrical Implications

Abstract

This paper reports on novel thermal testbeds with embedded micropinfin heat sinks that were designed and microfabricated in silicon. Two micropinfin arrays were presented, each with a nominal pin height of 200 خ¼m and pin diameters of 90 خ¼m and 30 خ¼m. Singlephase and twophase thermal testing of the micropinfin array heat sinks were performed using deionized (DI) water as the coolant. The tested mass flow rate was 0.001 kg/s, and heat flux ranged from 30 W/cm2 to 470 W/cm2. The maximum heat transfer coefficient reached was 60 kW/m2 K. The results obtained from the two testbeds were compared and analyzed, showing that density of the micropinfins has a significant impact on thermal performance. The convective thermal resistance in the singlephase region was calculated and fitted to an empirical model. The model was then used to explore the tradeoff between the electrical and thermal performance in heat sink design.