Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

New diode could enable faster, more efficient electronics

13.10.2003


Engineers have designed a new diode that transmits more electricity than any other device of its kind, and the inspiration for it came from technology that is 40 years old.


Paul R. Berger



Unlike other diodes in its class, called tunnel diodes, the new diode is compatible with silicon, so manufacturers could easily build it into mainstream electronic devices such as cell phones and computers.

Industry has long sought to marry tunnel diodes with conventional electronics as a means to simplify increasingly complex circuits, explained Paul R. Berger, professor of electrical engineering and physics at Ohio State.


“Computer chips now are worse than the Los Angeles freeway, with wires running back and forth clogging the path of propagating signals,” Berger said. “At some point, things are going to come to a grinding halt, and chips won’t run any faster.”

Because this diode can replace some of the circuits on a typical chip, it could potentially simplify chip design without compromising performance.

“Essentially, manufacturers would get more bang for their buck,” Berger said.

Researchers around the world have toiled for decades to develop such a diode, which could enable fast, efficient electronics that run on low-power batteries by requiring fewer devices to perform the same function.

The new diode conducts 150,000 amps per square centimeter of its silicon-based material -- a rate three times higher than that of the only comparable silicon tunnel diode.

Berger designed the diode with a team of engineers from Ohio State, the Naval Research Laboratory, and the University of California, Riverside. They describe it in today’s issue of the journal Applied Physics Letters.

“Our goal was to develop a tunnel diode that could be built directly onto a traditional computer chip at minimal cost,” Berger said. “And we’ve achieved that.”

Tunnel diodes are so named because they exploit a quantum mechanical effect known as tunneling, which lets electrons pass through barriers unhindered. The first tunnel diodes were created in the 1960s, and led to a Nobel Prize for physicist Leo Esaki in 1973.

Since then, in an effort to build more powerful diodes, researchers have increasingly turned to expensive, exotic materials that aren’t compatible with silicon, but allow tailored properties not often available in silicon.

Most modern tunnel diodes are “intraband” diodes, meaning they restrict the movements of electrons to one energy level, or “band,” within the semiconductor crystal. But the Esaki tunnel diodes were “interband” diodes -- they permitted electrons to pass back and forth between different energy bands.

At first, Berger’s team tried to develop intraband diodes with silicon technology. But faced with what he called a “materials science nightmare,” they turned instead to Esaki’s early tunnel diode technology for inspiration.

To construct a powerful interband diode, Berger’s team had to develop a new technique for creating silicon structures that contain unusually large quantities of other chemical elements, or dopants, such as boron and phosphorus.

“Essentially, we traded one nightmare for another,” Berger said with a laugh. “Mother Nature doesn’t want that much dopant in one place, but the doping problem was one that we felt we could tackle.”

They layered silicon and silicon-germanium into a structure that measured only a few nanometers, or billionths of a meter, high. Then they discovered that by changing the thickness of a central “spacer” layer, where the electrons are tunneling, they could tailor the amount of current that passed through the material. This had to be tempered with a design that kept the boron and phosphorus from intermixing.

Berger said that the diode’s ability to operate in low-power conditions makes it ideal for use in power-hungry devices that generate radio-frequency signals, such as cordless home telephones and cell phones. With little power input, the diode could generate a strong signal.

One other application that Berger finds particularly interesting involves medical devices. The diode could support a low-power data link that would let doctors perform diagnostics on pacemakers and other implants by remote, without wires protruding through a patient’s skin that could cause infections.

Co-authors on the paper included electrical engineering graduate students Niu Jin, Sung-Yong Chung, and Anthony T. Rice, and physics graduate student Ronghua Yu, all of Ohio State; Phillip E. Thompson of the Naval Research Lab; and Roger Lake of the University of California, Riverside.

This work was sponsored by the National Science Foundation and the Office of Naval Research. Berger will continue work supported by NSF and a major electronics company to develop wireless applications for the technology. Depending on that initial development, the technology could reach consumers anywhere from five to 15 years from now.

#

Contact: Paul R. Berger, (614) 247-6235; pberger@ieee.org

Written by Pam Frost Gorder, (614) 292-9475; Gorder.1@osu.edu

Pam Frost Gorder | OSU
Further information:
http://researchnews.osu.edu/archive/diode.htm
http://www.eleceng.ohio-state.edu/%7Eberger/
http://www.eleceng.ohio-state.edu/

More articles from Power and Electrical Engineering:

nachricht Organic-inorganic heterostructures with programmable electronic properties
29.03.2017 | Technische Universität Dresden

nachricht Researchers use light to remotely control curvature of plastics
23.03.2017 | North Carolina State University

All articles from Power and Electrical Engineering >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: A Challenging European Research Project to Develop New Tiny Microscopes

The Institute of Semiconductor Technology and the Institute of Physical and Theoretical Chemistry, both members of the Laboratory for Emerging Nanometrology (LENA), at Technische Universität Braunschweig are partners in a new European research project entitled ChipScope, which aims to develop a completely new and extremely small optical microscope capable of observing the interior of living cells in real time. A consortium of 7 partners from 5 countries will tackle this issue with very ambitious objectives during a four-year research program.

To demonstrate the usefulness of this new scientific tool, at the end of the project the developed chip-sized microscope will be used to observe in real-time...

Im Focus: Giant Magnetic Fields in the Universe

Astronomers from Bonn and Tautenburg in Thuringia (Germany) used the 100-m radio telescope at Effelsberg to observe several galaxy clusters. At the edges of these large accumulations of dark matter, stellar systems (galaxies), hot gas, and charged particles, they found magnetic fields that are exceptionally ordered over distances of many million light years. This makes them the most extended magnetic fields in the universe known so far.

The results will be published on March 22 in the journal „Astronomy & Astrophysics“.

Galaxy clusters are the largest gravitationally bound structures in the universe. With a typical extent of about 10 million light years, i.e. 100 times the...

Im Focus: Tracing down linear ubiquitination

Researchers at the Goethe University Frankfurt, together with partners from the University of Tübingen in Germany and Queen Mary University as well as Francis Crick Institute from London (UK) have developed a novel technology to decipher the secret ubiquitin code.

Ubiquitin is a small protein that can be linked to other cellular proteins, thereby controlling and modulating their functions. The attachment occurs in many...

Im Focus: Perovskite edges can be tuned for optoelectronic performance

Layered 2D material improves efficiency for solar cells and LEDs

In the eternal search for next generation high-efficiency solar cells and LEDs, scientists at Los Alamos National Laboratory and their partners are creating...

Im Focus: Polymer-coated silicon nanosheets as alternative to graphene: A perfect team for nanoelectronics

Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are less stable. Now researchers at the Technical University of Munich (TUM) have, for the first time ever, produced a composite material combining silicon nanosheets and a polymer that is both UV-resistant and easy to process. This brings the scientists a significant step closer to industrial applications like flexible displays and photosensors.

Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

International Land Use Symposium ILUS 2017: Call for Abstracts and Registration open

20.03.2017 | Event News

CONNECT 2017: International congress on connective tissue

14.03.2017 | Event News

ICTM Conference: Turbine Construction between Big Data and Additive Manufacturing

07.03.2017 | Event News

 
Latest News

Researchers shoot for success with simulations of laser pulse-material interactions

29.03.2017 | Materials Sciences

Igniting a solar flare in the corona with lower-atmosphere kindling

29.03.2017 | Physics and Astronomy

As sea level rises, much of Honolulu and Waikiki vulnerable to groundwater inundation

29.03.2017 | Earth Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>