Maxwell Labs has introduced a groundbreaking approach to cooling computer chips, harnessing the power of laser-assisted cooling to tackle one of the semiconductor industry’s most pressing challenges: heat dissipation. This unique approach overcomes the dark silicon challenge which has plagued the industry for more than two decades. Not only does it lead to more innovative and efficient chip designs, but it increases performance across the board.
Second, the semiconductor sector has been fighting a high-stakes, national race against a very serious problem. At a time when up to 80 percent of transistors on modern chips need to remain inactive or “dark” to prevent excessive heat generation. As it stands, current-generation chips typically reach temperature hot spots between 90 and 120 °C. Given the ever-increasing appetite for processing power, that concern is sure to worsen over time. Maxwell Labs’ new technique seeks to maintain chip temperatures below 50 °C across the board, while still achieving maximum performance along with the desired high efficiency.
By using photonic cooling to attack these hot spots at their source, Maxwell Labs believes it can fundamentally change the way chips are designed. Laser-assisted technology addresses the overheating concern directly. It further opens up the possibility for far greater clocking frequencies than we can achieve today.
The Challenge of Dark Silicon
For more than two decades, the semiconductor industry has wrestled with the dark silicon curse. But chips are increasing in complexity, as we try to fit millions or even billions of transistors on a single chip. Yet somehow, keeping cool has become a Herculean feat. The requirement for most transistors to be off at any moment introduces a huge performance and efficiency penalty.
In traditional cooling solutions, such as air and liquid cooling systems, maintaining acceptable temperatures for all active components proves challenging. The introduction of laser-assisted cooling could provide a significant breakthrough by allowing chips to operate at higher capacities without overheating.
Excessive heat from transistors can cause performance throttling and premature death of chips. Maxwell Labs approaches this issue head on. Their approach does a better job of cooling chips while saving energy at the same time. Preliminary results indicate that even this first generation unit can dissipate twice the power of conventional cooling methods. This development would realize more than a 50 percent decrease in total energy use.
The Mechanics of Laser-Assisted Cooling
Maxwell Labs proposes to implement its innovative technology using a grid of photonic cold plates strategically placed atop chip substrates. Each photonic cold plate is made of many closely spaced tiles 100 by 100 micrometers wide that help the cooling work more efficiently.
These cold plates incorporate several key components: a coupler, extractor, back reflector, and sensor. Together, they enable the anti-Stokes cooling process, which works by reemitting higher-energy photons. This unique process involves the integration of energy from incoming photons and phonons, resulting in highly efficient heat dissipation.
The phenomenon of anti-Stokes cooling was first demonstrated in 1995 when researchers managed to cool an ytterbium-doped fluoride glass sample using laser light. Since then, technological advances in the field of photonics have dramatically changed chances of applying this idea to semiconductor cooling. By harnessing this microprocessor technology, Maxwell Labs intends to achieve dramatic increases in chip performance.
Potential Impact on Energy Recovery
Beyond enabling further cooling, laser-assisted technology shows promise for energy recovery using thermophotovoltaics. This unique process recovers energy otherwise lost in operation. This, in turn, enables it to attain energy recovery rates exceeding 60 percent. These breakthroughs would greatly promote the sustainability and efficiency of semiconductor manufacturing and use.
Maxwell Labs laser-assisted cooling has larger implications beyond just keeping things cool. Now manufacturers are able to produce ever smaller and more powerful chips. They do this by keeping all of a chip’s parts operating at cooler than normal temperatures, sidestepping the restrictions imposed by existing cooling methods. This last discovery would open the gates to a new class of devices supporting better adaptability, interactivity and environmental footprint.