Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

New light-emitting transistor could revolutionize electronics industry

06.01.2004


Put the inventor of the light-emitting diode and the maker of the world’s fastest transistor together in a research laboratory and what kinds of bright ideas might surface? One answer is a light-emitting transistor that could revolutionize the electronics industry.




Professors Nick Holonyak Jr. and Milton Feng at the University of Illinois at Urbana-Champaign have uncovered a light-emitting transistor that could make the transistor the fundamental element in optoelectronics as well as in electronics. The scientists report their discovery in the Jan. 5 issue of the journal Applied Physics Letters.

“We have demonstrated light emission from the base layer of a heterojunction bipolar transistor, and showed that the light intensity can be controlled by varying the base current,” said Holonyak, a John Bardeen Professor of Electrical and Computer Engineering and Physics at Illinois. Holonyak invented the first practical light-emitting diode and the first semiconductor laser to operate in the visible spectrum.


“This work is still in the early stage, so it is not yet possible to say what all the applications will be,” Holonyak said. “But a light-emitting transistor opens up a rich domain of integrated circuitry and high-speed signal processing that involves both electrical signals and optical signals.”

A transistor usually has two ports: one for input and one for output. “Our new device has three ports: an input, an electrical output and an optical output,” said Feng, the Holonyak Professor of Electrical and Computer Engineering at Illinois. “This means that we can interconnect optical and electrical signals for display or communication purposes.” Feng is credited with creating the world’s fastest bipolar transistor, a device that operates at a frequency of 509 gigahertz.

Graduate student Walid Hafez fabricated the light-emitting transistor in the university’s Micro and Nanotechnology Laboratory. Unlike traditional transistors, which are built from silicon and germanium, the light-emitting transistors are made from indium gallium phosphide and gallium arsenide.

“In a bipolar device, there are two kinds of injected carriers: negatively charged electrons and positively charged holes,” Holonyak said. “Some of these carriers will recombine rapidly, supported by a base current that is essential for the normal transistor function.”

The recombination process in indium gallium phosphide and gallium arsenide materials also creates infrared photons, the “light” in the researchers’ light-emitting transistors. “In the past, this base current has been regarded as a waste current that generates unwanted heat,” Holonyak said. “We’ve shown that for a certain type of transistor, the base current creates light that can be modulated at transistor speed.”

Although the recombination process is the same as that which occurs in
light-emitting diodes, the photons in light-emitting transistors are generated under much higher speed conditions. So far, the researchers have demonstrated the modulation of light emission in phase with a base current in transistors operating at a frequency of 1 megahertz. Much higher speeds are considered certain.

“At such speeds, optical interconnects could replace electrical wiring between electronic components on a circuit board,” Feng said. This work could be the beginning of an era in which photons are directed around a chip in much the same fashion as electrons have been maneuvered on conventional chips.

“In retrospect, we could say the groundwork for this was laid more than 56 years ago with John Bardeen and Walter Brattain and their first germanium transistor,” said Holonyak, who was Bardeen’s first graduate student. “But the direct recombination involving a photon is weak in germanium materials, and John and Walter just wouldn’t have seen the light – even if they had looked. If John were alive and we showed him this device, he would have to have a big grin.”

James E. Kloeppel | UIUC
Further information:
http://www.news.uiuc.edu/news/04/0105LET.html

More articles from Power and Electrical Engineering:

nachricht New graphene-based metasurface capable of independent amplitude and phase control of light
20.02.2020 | The Korea Advanced Institute of Science and Technology (KAIST)

nachricht A step towards controlling spin-dependent petahertz electronics by material defects
19.02.2020 | Max-Planck-Institut für Struktur und Dynamik der Materie

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 step towards controlling spin-dependent petahertz electronics by material defects

The operational speed of semiconductors in various electronic and optoelectronic devices is limited to several gigahertz (a billion oscillations per second). This constrains the upper limit of the operational speed of computing. Now researchers from the Max Planck Institute for the Structure and Dynamics of Matter in Hamburg, Germany, and the Indian Institute of Technology in Bombay have explained how these processes can be sped up through the use of light waves and defected solid materials.

Light waves perform several hundred trillion oscillations per second. Hence, it is natural to envision employing light oscillations to drive the electronic...

Im Focus: Freiburg researcher investigate the origins of surface texture

Most natural and artificial surfaces are rough: metals and even glasses that appear smooth to the naked eye can look like jagged mountain ranges under the microscope. There is currently no uniform theory about the origin of this roughness despite it being observed on all scales, from the atomic to the tectonic. Scientists suspect that the rough surface is formed by irreversible plastic deformation that occurs in many processes of mechanical machining of components such as milling.

Prof. Dr. Lars Pastewka from the Simulation group at the Department of Microsystems Engineering at the University of Freiburg and his team have simulated such...

Im Focus: Skyrmions like it hot: Spin structures are controllable even at high temperatures

Investigation of the temperature dependence of the skyrmion Hall effect reveals further insights into possible new data storage devices

The joint research project of Johannes Gutenberg University Mainz (JGU) and the Massachusetts Institute of Technology (MIT) that had previously demonstrated...

Im Focus: Making the internet more energy efficient through systemic optimization

Researchers at Chalmers University of Technology, Sweden, recently completed a 5-year research project looking at how to make fibre optic communications systems more energy efficient. Among their proposals are smart, error-correcting data chip circuits, which they refined to be 10 times less energy consumptive. The project has yielded several scientific articles, in publications including Nature Communications.

Streaming films and music, scrolling through social media, and using cloud-based storage services are everyday activities now.

Im Focus: New synthesis methods enhance 3D chemical space for drug discovery

After helping develop a new approach for organic synthesis -- carbon-hydrogen functionalization -- scientists at Emory University are now showing how this approach may apply to drug discovery. Nature Catalysis published their most recent work -- a streamlined process for making a three-dimensional scaffold of keen interest to the pharmaceutical industry.

"Our tools open up whole new chemical space for potential drug targets," says Huw Davies, Emory professor of organic chemistry and senior author of the paper.

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

70th Lindau Nobel Laureate Meeting: Around 70 Laureates set to meet with young scientists from approx. 100 countries

12.02.2020 | Event News

11th Advanced Battery Power Conference, March 24-25, 2020 in Münster/Germany

16.01.2020 | Event News

Laser Colloquium Hydrogen LKH2: fast and reliable fuel cell manufacturing

15.01.2020 | Event News

 
Latest News

Active droplets

21.02.2020 | Medical Engineering

Finding new clues to brain cancer treatment

21.02.2020 | Health and Medicine

Beyond the brim, Sombrero Galaxy's halo suggests turbulent past

21.02.2020 | Physics and Astronomy

VideoLinks
Science & Research
Overview of more VideoLinks >>>