Subscribe free to our newsletters via your
. 24/7 Space News .

Subscribe free to our newsletters via your

Real-time monitoring of surface changes at the atomic level
by Staff Writers
Washington DC (SPX) Mar 22, 2016

File image.

A team of researchers at Aix Marseille Universite in Marseille, France led by Dr. Frederic Leroy developed a technique that allows them to follow physical processes occurring at surfaces of materials at the atomic level in situ and in real time. This new process allowed the research team to study the kinetics of decomposition of a thin layer of silicon dioxide deposited onto silicon during a thermal treatment, a critical component in micro-electronics. The approach is based on the principles of electron microscopy.

Silicon dioxide is one of the most important building blocks of micro-electronics and its thermal stability is critical to device performance. The decomposition of a thin layer of silicon dioxide onto silicon has been the focus of great scientific interest for four decades.

Previous studies show that the decomposition occurs non-homogeneously at the surface via the local formation of holes in the oxide layer that extend laterally. Understanding the elementary atomic processes responsible for the opening velocity of these holes is necessary to improve the silicon oxide performance.

For the research team to achieve a better understanding of nanomaterials properties, advanced characterization tools were needed.

"We needed to be able to characterize the structural (crystallography, size, shape) and the chemical properties at the same time and to be able to follow in situ and in real time the changes during a given process for a rapid feedback on the experimental parameters," Leroy explained. "Our approach based on low energy electron microscopy is the corner stone of our achievements."

However, even with the new instrument, the team encountered challenges. Obtaining real time measurements of the thermal decomposition of the silicon dioxide was particularly difficult since the complete process occurs in just a few minutes in a narrow temperature window.

"It was impossible to adjust all control parameters of the electron microscope before the decomposition process started since silicon dioxide is amorphous, so we had to adjust finely the settings within a few seconds as soon as the oxide decomposes in order to characterize the whole process," Leroy explained.

However, the meticulous measurement yielded some surprising results. Leroy and his research team found experimental evidence that the decomposition process was not initially in a steady state regime as previous studies had argued.

"Our results imply that the conventional view of a steady state regime for the silicon dioxide decomposition related to a simplified reaction Si+SiO2-> 2SiO(g) occurring at the hole edge is not generally true," Leroy said.

Instead, the team's results imply that silicon dioxide decomposition occurs via hole nucleation and opening with a circular shape. The velocity of holes opening is intimately related to the decomposition rate of silicon dioxide at the periphery of the holes.

Initially, large holes open fast thanks to a chemical reaction catalyzed by species such as Si hydroxyls present inside the hole. Researchers suspect these species agglomerate during long thermal annealing and are released inside the holes during the silicon dioxide decomposition.

The main applications of this work are in micro-electronics, particularly all steps of thermal treatments.

"We have shown that the silicon dioxide formed by a wet chemical treatment is highly defective after a long thermal annealing," Leroy said. "The next step in our research is to study the interplay between chemical reactions and the enhancement of the mobility of nanostructures."

The article, "Catalytically enhanced thermal decomposition of chemically grown silicon 2 oxide layers on Si(001)," is authored by F. Leroy, T. Passanante, F. Cheynis, S. Curiotto, E. B. Bussmann and P. Muller. It will be published in the journal Applied Physics Letters March 15, 2016 (DOI:10.1063/1.4941799).

Thanks for being here;
We need your help. The SpaceDaily news network continues to grow but revenues have never been harder to maintain.

With the rise of Ad Blockers, and Facebook - our traditional revenue sources via quality network advertising continues to decline. And unlike so many other news sites, we don't have a paywall - with those annoying usernames and passwords.

Our news coverage takes time and effort to publish 365 days a year.

If you find our news sites informative and useful then please consider becoming a regular supporter or for now make a one off contribution.

SpaceDaily Contributor
$5 Billed Once

credit card or paypal
SpaceDaily Monthly Supporter
$5 Billed Monthly

paypal only


Related Links
American Institute of Physics
Understanding Time and Space

Comment on this article via your Facebook, Yahoo, AOL, Hotmail login.

Share this article via these popular social media networks DiggDigg RedditReddit GoogleGoogle

Previous Report
Theoretical physics discovery to set the research field buzzing
Cincinnati OH (SPX) Mar 21, 2016
Bazinga! University of Cincinnati theoretical physicists are about to report on a controversial discovery that they say contradicts the work of researchers over the decades. The discovery concerns the conventional approach toward bosonization-debosonization. For folks outside the physics lab and the whiteboard, this could affect calculations regarding the future of quantum computers as wel ... read more

Permanent Lunar Colony Possible in 10 Years

China to use data relay satellite to explore dark side of moon

NASA May Return to Moon, But Only After Cutting Off ISS

Lunar love: When science meets artistry

How the ExoMars mission could sniff out life on Mars

ExoMars on its way to solve the Red Planet's mysteries

Europe's New Mars Mission Bringing NASA Radios Along

Close comet flyby threw Mars' magnetic field into chaos

Broomstick flying or red-light ping-pong? Gadgets at German fair

Jacobs Joins Coalition for Deep Space Exploration

Accelerating discovery with new tools for next generation social science

Space Race Competition helps turn NASA Tech into new products

China's ambition after space station

Sky is the limit for China's national strategy

Aim Higher: China Plans to Send Rover to Mars in 2020

China's lunar probe sets record for longest stay

Three new crew, including US grandpa, join space station

Space station astronauts ham it up to inspire student scientists

Roscosmos-NASA Contract on US Astronauts Delivery to ISS on Restructuring

NASA station leads way for improved measurements of Earth orientation, shape

Launch of Dragon Spacecraft to ISS Postponed Until April

ILS and INMARSAT Agree To Future Proton Launch

Soyuz 2-1B Carrier Rocket Launched From Baikonur

ISRO launches PSLV C32, India's sixth navigation satellite

NASA's K2 mission: Kepler second chance to shine

Star eruptions create and scatter elements with Earth-like composition

Astronomers discover two new 'hot Jupiter' exoplanets

Sharpest view ever of dusty disc around aging star

A foldable material that can change size, volume and shape

The world's blackest material is now in spray form

New insights into atomic disordering of complex metal oxides

How to make porous materials dry faster

Memory Foam Mattress Review
Newsletters :: SpaceDaily :: SpaceWar :: TerraDaily :: Energy Daily
XML Feeds :: Space News :: Earth News :: War News :: Solar Energy News

The content herein, unless otherwise known to be public domain, are Copyright 1995-2017 - Space Media Network. All websites are published in Australia and are solely subject to Australian law and governed by Fair Use principals for news reporting and research purposes. AFP, UPI and IANS news wire stories are copyright Agence France-Presse, United Press International and Indo-Asia News Service. ESA news reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. All articles labeled "by Staff Writers" include reports supplied to Space Media Network by industry news wires, PR agencies, corporate press officers and the like. Such articles are individually curated and edited by Space Media Network staff on the basis of the report's information value to our industry and professional readership. Advertising does not imply endorsement, agreement or approval of any opinions, statements or information provided by Space Media Network on any Web page published or hosted by Space Media Network. Privacy Statement