Moore's Law Survives? Microfluidic Cooling May Keep Its Promise Alive

For much of the digital age, "Moore's law" has held sway. That is, the number of transistors that can be accommodated on an integrated circuit is a number that has doubled every two years. Computer engineers have been expecting this number to hit its limit, but there's hope yet, due to a new advance: microfluidic cooling.

The engineering challenge posed by placing more and more transistors in a silicon chip involves electron flow resistance. As a current of electrons moves through the circuitry, it encounters electrical resistance, which results in the chip heating up. The more transistors you put on a chip, the more the heat becomes a problem - and too much heat can damage the microchip architecture.

The Defense Advanced Research Projects Agency (DARPA) has been looking for a solution to the heating issue. The agency has put its resources behind a program called ICECool Applications, where ICECool stands for "Intra/Interchip Enhanced Cooling."

The general idea is to equip microchips with cold plates that have embedded thermal management systems which facilitate heat removal on the chip level, using coolant liquids. The micro-cooler architecture makes use of micro-pores and integrated channels and even liquid jets, a design that allows coolant to be be distributed in a controlled manner to effectively reduce the heat in the system.

"What is unique about this method of cooling is the push to use a combination of intra- and/or inter-chip microfluidic cooling and on-chip thermal interconnects," notes TechRepublic in its review of the concept. Or as the aerospace company Lockheed Martin refers to it, a "just add water" approach. Very little water, as it turns out - the liquid-cooled cold plates need less than a drop of water to function.

Lockheed Martin has, in experiments, verified the effectiveness of ICECool in reducing resistance four-fold in a thermal demonstration "die" (an electronic chip). The firm also tested the microfluidic cooling tech in radio frequency amplifiers. The result: the ICECool-equipped amplifier generated six times the output power of a standard amplifier, while also running cooler.

If microfluidic cooling proves to be both an effective and commercially viable application, it will do more than keep Moore's law relevant. In time, this can make our mobile and wearable gadgets even smaller, lighter, and less demanding of energy than they are now.