3D printed cooler outperforms conventional solutions

By Warren Miller, contributing writer

As chips and
electronic systems continue to cross thresholds of higher and higher
performance, they need to manage an inevitable byproduct: heat. As more
traditional cooling methods prove less effective, chip designers and
manufacturers are looking for efficient, cost-effective solutions to their
cooling problems. Imec, an international collaborative research hub, recently
introduced an innovative new cooling technique that could provide an answer.

Current
cooling solutions rely on heat exchangers and spreaders attached to the back of
chips to distribute the heat evenly along the surface of the chip. This is an
important consideration – any temperature differential degrades performance and
long-term viability, making direct cooling of the chip a less than ideal
solution.

Liquid
coolants must be distributed evenly across and perpendicular to the chip’s
surface to maintain an equal temperature and to cut down cooling time — a
process commonly performed by impingement coolers. These impingement-based
cooling systems have typically been silicon-based, making them cost inefficient
to produce, said Imec.

Imec’s
solution to this persistent problem is a polymer-based impingement chip cooler
produced by a high-resolution stereolithography 3D printer that features nozzle sizes of only 300 µm. The nozzle pattern design can be
customized to suit the specifications of a chip design. By using a 3D printer,
the entire structure can be printed as a single part, significantly lessening
both production time and costs, said Imec. 

Image source: Imec.

The new
design has outperformed industry standards by a significant margin. While more
traditional cooling systems and thermal interface materials produce a
temperature increase of anywhere from 20°C to 50°C, the Imec impingement cooler
boasts a temperature increase of less than 15°C per 100 W/cm2 at a coolant flow
rate of one liter per minute, and delivers a pressure drop as low as 0.3 bar. In
addition to its higher performance and lower cost, the Imec system is also
physically smaller than existing solutions, making it more in line with the
ever-miniaturizing world of chips and electronic systems.

Liquid
cooling isn’t a new concept, however. The first big mainframe computers from
IBM and Cray had complex liquid cooling systems that rivaled the complexity of
the electronics. In fact, Cray had more patents on cooling innovations than on
electronic ones for its biggest computers. These cooling systems took up much
more space than the innovative approach Imec has identified.

More
efficient cooling means better, longer-lasting performance, which means Imec’s
design could become the industry standard in short order. Cooling is a central
issue in high-resolution video and graphics systems, such as multimedia or
augmented reality/virtual reality (AR/VR) platforms. If the polymer-based
impingement cooler can find its way into those markets, it could become the
proverbial pot of gold at the end of the rainbow.