Direct Single Impinging Jet Cooling of a <sc>mosfet</sc> Power Electronic Module

Abstract

This paper presents an approach of direct liquid jet impingement cooling of a typical MOSFET power module. A single micro water jet was installed for cooling the upper surface of a MOSFET semiconductor package. In contrast to standard cooling methods, this approach focuses on hot spot removal omitting any kind of heat spreading device. The cooling chamber was directly soldered to the MOSFET cover that represents a very efficient way of liquid cooling. Two different configurations with and without electrical insulation (TIM) were used to investigate the importance of insulating material. In the range of 10-100 mL/min coolant flow rates at an inlet temperature of 22.5 °C a maximum power distribution of 51 W (at 30 mL/min) next to a maximum measured MOSFET temperature of 163 °C could be realized. Heat transfer coefficients up to 12 000 W/m <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> · K were achieved using only 10.8 cm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sup> of assembly space for the cooling device. With electrical insulation, the heat transfer coefficient exceeded 6000 W/m <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> · K at a coolant flow rate of 30 mL/min and pumping power of 3 mW. The results illustrate the potential of direct liquid cooling using impinging microjets in combination with a compact injection chamber. The individual cooling of semiconductors offers new perspectives in the design of power electronic modules.