The Defence Advanced Research Projects Agency (DARPA) is supporting new research to provide on-chip liquid cooling in field-programmable gate array (FPGA) devices and it looks like the technology could be easily adapted for CPUs and GPUs.
This has the potential to reduce the size of devices, allow for chip stacking, dispense with heat sinks and fans and significantly extend the life-span of chips.
Speaking at the IEEE Custom Integrated Circuits Conference, Thomas Sarvey, from Georgia Institute of Technology (GIT) presented the paper with the catchy title “Embedded Cooling Technologies for Densely Integrated Electronic Systems.”
What they managed to do was get rid of the heat sink atop the silicon die by moving liquid cooling just a few hundred microns away from the transistors.
The technique involves cutting microfluidic channels into the die of FPGA devices, which were chosen for the research and trials because of their flexible configuration and extensive use in the military.
This locates the cooling just microns from the problem, and even allows for the possibility of chip-stacking, which very few devices currently have the room or efficiency to achieve, given the necessity to dissipate heat from a central locus of adjacent chips.
The group successfully developed a standard demonstration test, including one for DARPA officials, in which a converted FPGA with bespoke Altera-supplied architecture operated, with no other cooling, at less than 24 degrees Celsius, and was compared to an analogous air-cooled device operating at 60 degrees Celsius.
On-chip liquid cooling also opens up the possibility for a new level of compactness in device design, which frequently has to use available surface space for dissipation purposes.