Hotspot Liquid Microfluidic Cooling: Comparing The Efficiency between Horizontal Flow and Vertical Flow

This paper reports a novel cooling method for a local high-temperature block in an integrated circuit, which is called a “hotspot”. The method is to cool the chip in out-of-plane (3-D) direction to overcome efficiency limit of traditional horizontal (2-D) cooling. Our result indicates that high-temperature (over 180 °C) circuit block such as a phase-locked-loop (PLL), which is a performance limiting block in a modern CPU, can more efficiently be cooled by the vertical (3-D) cooling scheme.