New computer switches handle heat that renders transistors useless

Oct 07, 2010

Researchers at Case Western Reserve University have taken the first step to building a computer capable of operating in the heat of a jet engine or the sunny side of the planet Mercury.

Te-Hao Lee, Swarup Bhunia and Mehran Mehregany, have made electromechanical – building blocks of circuits - that can take twice the that renders electronic transistors useless. Their work was published in Science last month.

The engineers took their cue from English inventor Charles Babbage, who built a steam-driven machine to calculate mathematical tables in the 1830s. The group applied nanotechnology to make switches fit today's ever-smaller computing platforms.

After configuring the switches into an inverter, they found the devices continue to work at more than 500 degrees Celsius - resilient enough to work inside engines of cars, jets and rockets, in deep underground drilling, even on the surface of Venus and Mercury.

"They work because they're mechanical and made of silicon carbide, which is robust at high temperatures," Bhunia said. "The switches operate in high heat and radiation, at lower voltage and higher density and perform better than transistors designed to operate in high heat."

While transistors have the advantage of no moving parts, they deteriorate at about 250 degree Celsius and leak electrons excited by the warmth, voiding the ability to accurately relay the current that moves data in computers.

To avoid those problems Lee, a PhD student, and Bhunia and Mehregany, professors of electrical engineering and computer science, decided to build switches of heat tolerant material and in a form in which, much like a light switch, mechanical levers make contact to pass current or break contact to halt current.

The group used electron beam lithography and sulfur hexafluoride gas to etch the switches, just a few hundred nanometers in size, out of silicon carbide.

The result is a switch that has no discernable leakage and no loss of power in testing at 500 degrees Celsius.

A pair of switches were used to make an inverter, which was able to switch on and off 500,000 times per second, performing computation each cycle. The switches, however, began to break down after 2 billion cycles and in a manner the researchers do not yet fully understand.

"We made a building block," Bhunia said. "Next, we're trying to make memory. If we can combine them, we can build a computer."

He and the others are confident that with improvements in production, they can build more durable switches that can cycle faster.

Whether they can reach the point of competing with faster transistors for office and home and even supercomputing, remains to be seen. The researchers point out that with the ability to handle much higher heat, the need for costly and space-consuming cooling systems would be eliminated.

Explore further: PsiKick's batteryless sensors poised for coming 'Internet of things'

add to favorites email to friend print save as pdf

Related Stories

Mechanical logic gate: Could levers replace transistors?

Sep 17, 2010

(PhysOrg.com) -- Back in the Victorian period, Charles Babbage created a mechanical computer that made use of levers and cogs to get data moving. These days, though, our computers are mostly run using electronic ...

NXP drives energy efficiency with bipolar transistors

Mar 14, 2007

NXP, the independent semiconductor company founded by Philips, today announced the availability of its latest generation of low VCEsat transistors, which reduces power loss by 80 percent compared to general purpose transistors.

Team develops tiny optical switch

Dec 20, 2007

A team of researchers at the University of St. Andrews has developed one of the smallest optical switches ever made.

Recommended for you

Large streams of data warn cars, banks and oil drillers

Apr 16, 2014

Better warning systems that alert motorists to a collision, make banks aware of the risk of losses on bad customers, and tell oil companies about potential problems with new drilling. This is the aim of AMIDST, the EU project ...

User comments : 0

More news stories

Hackathon team's GoogolPlex gives Siri extra powers

(Phys.org) —Four freshmen at the University of Pennsylvania have taken Apple's personal assistant Siri to behave as a graduate-level executive assistant which, when asked, is capable of adjusting the temperature ...

Better thermal-imaging lens from waste sulfur

Sulfur left over from refining fossil fuels can be transformed into cheap, lightweight, plastic lenses for infrared devices, including night-vision goggles, a University of Arizona-led international team ...

Chronic inflammation linked to 'high-grade' prostate cancer

Men who show signs of chronic inflammation in non-cancerous prostate tissue may have nearly twice the risk of actually having prostate cancer than those with no inflammation, according to results of a new study led by researchers ...