Nanotechnology Now

Our NanoNews Digest Sponsors
Heifer International

Wikipedia Affiliate Button

Home > Press > Getting electrons to move in a semiconductor: Gallium oxide shows high electron mobility, making it promising for better and cheaper devices

Schematic stack and the scanning electron microscopic image of the β-(AlxGa1-x)2O3/Ga2O3 modulation-doped field effect transistor.
CREDIT
Choong Hee Lee and Yuewei Zhang
Schematic stack and the scanning electron microscopic image of the β-(AlxGa1-x)2O3/Ga2O3 modulation-doped field effect transistor. CREDIT Choong Hee Lee and Yuewei Zhang

Abstract:
The next generation of energy-efficient power electronics, high-frequency communication systems, and solid-state lighting rely on materials known as wide bandgap semiconductors. Circuits based on these materials can operate at much higher power densities and with lower power losses than silicon-based circuits. These materials have enabled a revolution in LED lighting, which led to the 2014 Nobel Prize in physics.

Getting electrons to move in a semiconductor: Gallium oxide shows high electron mobility, making it promising for better and cheaper devices

Washington, DC | Posted on April 24th, 2018

In new experiments reported in Applied Physics Letters, from AIP Publishing, researchers have shown that a wide-bandgap semiconductor called gallium oxide (Ga2O3) can be engineered into nanometer-scale structures that allow electrons to move much faster within the crystal structure. With electrons that move with such ease, Ga2O3 could be a promising material for applications such as high-frequency communication systems and energy-efficient power electronics.

"Gallium oxide has the potential to enable transistors that would surpass current technology," said Siddharth Rajan of Ohio State University, who led the research.

Because Ga2O3 has one of the largest bandgaps (the energy needed to excite an electron so that it's conductive) of the wide bandgap materials being developed as alternatives to silicon, it's especially useful for high-power and high-frequency devices. It's also unique among wide bandgap semiconductors in that it can be produced directly from its molten form, which enables large-scale manufacturing of high-quality crystals.

For use in electronic devices, the electrons in the material must be able to move easily under an electric field, a property called high electron mobility. "That's a key parameter for any device," Rajan said. Normally, to populate a semiconductor with electrons, the material is doped with other elements. The problem, however, is that the dopants also scatter electrons, limiting the electron mobility of the material.

To solve this problem, the researchers used a technique known as modulation doping. The approach was first developed in 1979 by Takashi Mimura to create a gallium arsenide high-electron mobility transistor, which won the Kyoto Prize in 2017. While it is now a commonly used technique to achieve high mobility, its application to Ga2O3 is something new.

In their work, the researchers created a so-called semiconductor heterostructure, creating an atomically perfect interface between Ga2O3 and its alloy with aluminum, aluminum gallium oxide -- two semiconductors with the same crystal structure but different energy gaps. A few nanometers away from the interface, embedded inside the aluminum gallium oxide, is a sheet of electron-donating impurities only a few atoms thick. The donated electrons transfer into the Ga2O3, forming a 2-D electron gas. But because the electrons are now also separated from the dopants (hence the term modulation doping) in the aluminum gallium oxide by a few nanometers, they scatter much less and remain highly mobile.

Using this technique, the researchers reached record mobilities. The researchers were also able to observe Shubnikov-de Haas oscillations, a quantum phenomenon in which increasing the strength of an external magnetic field causes the resistance of the material to oscillate. These oscillations confirm formation of the high mobility 2-D electron gas and allow the researchers to measure critical material properties.

Rajan explained that such modulation-doped structures could lead to a new class of quantum structures and electronics that harnesses the potential of Ga2O3.

####

About American Institute of Physics
Applied Physics Letters features concise, rapid reports on significant new findings in applied physics. The journal covers new experimental and theoretical research on applications of physics phenomena related to all branches of science, engineering, and modern technology. See http://apl.aip.org .

For more information, please click here

Contacts:
Julia Majors

301-209-3090

Copyright © American Institute of Physics

If you have a comment, please Contact us.

Issuers of news releases, not 7th Wave, Inc. or Nanotechnology Now, are solely responsible for the accuracy of the content.

Bookmark:
Delicious Digg Newsvine Google Yahoo Reddit Magnoliacom Furl Facebook

Related Links

The article, "Demonstration of high mobility and quantum transport in modulation-doped β-(AlxGa1-x)2O3/Ga2O3 heterostructures," is authored by Yuewei Zhang, Adam Neal, Zhanbo Xia, Chandan Joishi, Yuanhua Zheng, Sanyam Bajaj, Mark Brenner, Shin Mou, Donald Dorsey, Kelson Chabak, Gregg Jessen, Jinwoo Hwang, Joseph Heremans and Siddarth Rajan. The article will appear in Applied Physics Letters April 24, 2018 (DOI: 10.1063/1.5025704). After that date, it can be accessed at:

Related News Press

News and information

Coal could yield treatment for traumatic injuries: Rice, Texas A&M, UTHealth scientists discover coal-derived ‘dots’ are effective antioxidant April 25th, 2019

Arrowhead Begins Triple Combination Cohort in Chronic HBV Patients and Earns $25 Million Milestone Payment from Janssen April 23rd, 2019

Micro-LEDs achieve superior brightness with Picosun’s ALD technology April 23rd, 2019

Scientists explore the unknown behaviour of gold nanoparticles with neutrons April 23rd, 2019

How slippery surfaces allow sticky pastes and gels to slide: Engineered surface treatment developed at MIT can reduce waste and improve efficiency in many processes April 23rd, 2019

Display technology/LEDs/SS Lighting/OLEDs

Micro-LEDs achieve superior brightness with Picosun’s ALD technology April 23rd, 2019

A hole in one for holographic display: Tiny pinholes in a thin film could pave the way for more widespread applications for 3D holographic displays April 19th, 2019

Fish-Inspired Material Changes Color Using Nanocolumns March 18th, 2019

Exotic spiraling electrons discovered by physicists: Rutgers-led research could lead to advances in lighting and solar cells February 18th, 2019

2 Dimensional Materials

From 2D to 1D: Atomically quasi '1D' wires using a carbon nanotube template: New bulk synthesis method for nanowires of molybdenum telluride for nanoelectronics April 19th, 2019

2D gold quantum dots are atomically tunable with nanotubes April 11th, 2019

2D borophene gets a closer look: Rice, Northwestern find new ways to image, characterize unique material April 11th, 2019

'Deep learning' casts wide net for novel 2D materials: Rice U. engineers show faster techniques to model atom-flat materials for bottom-up design April 10th, 2019

Hardware

Organic semiconductors: One transistor for all purposes March 22nd, 2019

Picosun’s ALD encapsulation prevents electronics degradation February 15th, 2019

Possible Futures

Coal could yield treatment for traumatic injuries: Rice, Texas A&M, UTHealth scientists discover coal-derived ‘dots’ are effective antioxidant April 25th, 2019

Arrowhead Begins Triple Combination Cohort in Chronic HBV Patients and Earns $25 Million Milestone Payment from Janssen April 23rd, 2019

Scientists explore the unknown behaviour of gold nanoparticles with neutrons April 23rd, 2019

How slippery surfaces allow sticky pastes and gels to slide: Engineered surface treatment developed at MIT can reduce waste and improve efficiency in many processes April 23rd, 2019

Chip Technology

From 2D to 1D: Atomically quasi '1D' wires using a carbon nanotube template: New bulk synthesis method for nanowires of molybdenum telluride for nanoelectronics April 19th, 2019

Improving quantum computers April 19th, 2019

2D gold quantum dots are atomically tunable with nanotubes April 11th, 2019

2D borophene gets a closer look: Rice, Northwestern find new ways to image, characterize unique material April 11th, 2019

Nanoelectronics

From 2D to 1D: Atomically quasi '1D' wires using a carbon nanotube template: New bulk synthesis method for nanowires of molybdenum telluride for nanoelectronics April 19th, 2019

2D borophene gets a closer look: Rice, Northwestern find new ways to image, characterize unique material April 11th, 2019

Organic semiconductors: One transistor for all purposes March 22nd, 2019

When semiconductors stick together, materials go quantum: A new study led by Berkeley Lab reveals how aligned layers of atomically thin semiconductors can yield an exotic new quantum material March 12th, 2019

Discoveries

Coal could yield treatment for traumatic injuries: Rice, Texas A&M, UTHealth scientists discover coal-derived ‘dots’ are effective antioxidant April 25th, 2019

Scientists explore the unknown behaviour of gold nanoparticles with neutrons April 23rd, 2019

How slippery surfaces allow sticky pastes and gels to slide: Engineered surface treatment developed at MIT can reduce waste and improve efficiency in many processes April 23rd, 2019

Coincidence helps with quantum measurements: New method enables quantum simulations on larger systems April 22nd, 2019

Materials/Metamaterials

Coal could yield treatment for traumatic injuries: Rice, Texas A&M, UTHealth scientists discover coal-derived ‘dots’ are effective antioxidant April 25th, 2019

Multistep self-assembly opens door to new reconfigurable materials April 19th, 2019

From nata de coco to computer screens: Cellulose gets a chance to shine: Researchers at Osaka University meticulously measured the optical birefringence of highly aligned cellulose nanofibers, paving the way for sharper television, computer, and smartphone screens April 19th, 2019

NEXUS 2019: Global Summit on Energy Materials and Green Nanotechnology April 16th, 2019

Announcements

Coal could yield treatment for traumatic injuries: Rice, Texas A&M, UTHealth scientists discover coal-derived ‘dots’ are effective antioxidant April 25th, 2019

Arrowhead Begins Triple Combination Cohort in Chronic HBV Patients and Earns $25 Million Milestone Payment from Janssen April 23rd, 2019

Micro-LEDs achieve superior brightness with Picosun’s ALD technology April 23rd, 2019

Scientists explore the unknown behaviour of gold nanoparticles with neutrons April 23rd, 2019

Interviews/Book Reviews/Essays/Reports/Podcasts/Journals/White papers

Coal could yield treatment for traumatic injuries: Rice, Texas A&M, UTHealth scientists discover coal-derived ‘dots’ are effective antioxidant April 25th, 2019

Scientists explore the unknown behaviour of gold nanoparticles with neutrons April 23rd, 2019

How slippery surfaces allow sticky pastes and gels to slide: Engineered surface treatment developed at MIT can reduce waste and improve efficiency in many processes April 23rd, 2019

Coincidence helps with quantum measurements: New method enables quantum simulations on larger systems April 22nd, 2019

Grants/Sponsored Research/Awards/Scholarships/Gifts/Contests/Honors/Records

Coal could yield treatment for traumatic injuries: Rice, Texas A&M, UTHealth scientists discover coal-derived ‘dots’ are effective antioxidant April 25th, 2019

From 2D to 1D: Atomically quasi '1D' wires using a carbon nanotube template: New bulk synthesis method for nanowires of molybdenum telluride for nanoelectronics April 19th, 2019

'Nanobodies' from alpacas could help bring CAR T-cell therapy to solid tumors: Unusually small antibodies, targeted to the tumor micro-environment, curb melanoma and colon cancer in mouse models April 11th, 2019

2D borophene gets a closer look: Rice, Northwestern find new ways to image, characterize unique material April 11th, 2019

NanoNews-Digest
The latest news from around the world, FREE



  Premium Products
NanoNews-Custom
Only the news you want to read!
 Learn More
NanoStrategies
Full-service, expert consulting
 Learn More











ASP
Nanotechnology Now Featured Books




NNN

The Hunger Project