Package-level Si-based micro-jet impingement cooling solution with multiple drainage micro-trenches

High heat flux removal is a major consideration in the design of a number of microelectronic devices. A Si micro cooler, combining the merits of both micro-channels and jet impingement, has been developed to dissipate the heat flux for the IC chip. Multiple drainage micro-trenches (MDMT) have been designed inside the cooler to avoid the negative cross-flow effect between the nearby nozzles. The effect of the micro-trench width on the required pressure drop is analyzed. Three types of nozzle/trench arrangements are studied. Several simulations are conducted to study the thermal effect of the distance between nozzle and trench, when the same pumping power is supplied. Without cross-flow effect, full developed jet impingement can be achieved for each nozzle. With 0.2W pumping power, the spatially average heat transfer coefficient is around 15×10⁴W/m²K. To dissipate 350W/cm² heat flux uniformly loaded on the Si chip, the designed micro cooler can maintain the maximum chip temperature rise lower than 25°C, and low temperature variation within the chip. The designed cooler with MDMT is also quite effective for cooling the chip with concentrated heat fluxes.