"BroadGroup Power and Cooling Summit in London, IBM researchers presented an innovative approach for improving the cooling of computer chips, an increasingly urgent need given the large amount of heat released by today's more powerful processors and the additional energy required for removing that heat.
The technique, called "high thermal conductivity interface technology," allows a twofold improvement in heat removal over current methods. This paves the way for continued development of creative electronic products through the use of more powerful chips without complex and costly systems simply to cool them.
The approach used by IBM addresses the connection point between the hot chip and the various cooling components used today to draw the heat away, including heat sinks. Special particle-filled viscous pastes are typically applied to this interface to guarantee that chips can expand and contract owing to the thermal cycling. This paste is kept as thin as possible in order to transport heat from chip to the cooling components efficiently. Yet, squeezing these pastes too thin between the cooling components and chip would damage or even crack the chip if the conventional technologies are used.
Using sophisticated micro-technology, the IBM researchers developed a chip cap with a network of tree-like branched channels on its surface. The pattern is designed such that when pressure is applied, the paste spreads much more evenly and the pressure remains uniform across the chip. This allows the right uniformity to be obtained with nearly two times less pressure, and a ten times better heat transport through the interface.
This unique and extremely powerful design for chip cooling is borrowed from biology. Systems of hierarchical channels can be found manifold in nature, e.g. tree leaves, roots, or the human circulatory system. They can serve very large volumes with little energy, which is crucial in all organisms larger than a few millimeters. Ancient water irrigation systems also used the same approach."
