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: Entrepreneur builds a sleek ship, but will anyone buy it?

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

Off-world manufacturing is a go with space printer

Dec 20, 2014

On Friday, the BBC reported on a NASA email exchange with a space station which involved astronauts on the International Space Station using their 3-D printer to make a wrench from instructions sent up in ...

First drone in Nevada test program crashes in demo

Dec 19, 2014

A drone testing program in Nevada is off to a bumpy start after the first unmanned aircraft authorized to fly without Federal Aviation Administration supervision crashed during a ceremony in Boulder City.

User comments : 0

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.