Nanotechnology Now

Our NanoNews Digest Sponsors


Heifer International

Wikipedia Affiliate Button


DHgate

Home > Press > New method monitors semiconductor etching as it happens – with light

Photo by Chris Edwards, Amir Arbabi, Gabriel Popescu, and Lynford Goddard

A three-dimensional image of an etched gallium-arsenide semiconductor, taken during etching with a new microscopy technique that monitors the etching process on the nanometer scale. The height difference between the orange and purple regions is approximately 250 nanometers.
Photo by Chris Edwards, Amir Arbabi, Gabriel Popescu, and Lynford Goddard

A three-dimensional image of an etched gallium-arsenide semiconductor, taken during etching with a new microscopy technique that monitors the etching process on the nanometer scale. The height difference between the orange and purple regions is approximately 250 nanometers.

Abstract:
University of Illinois researchers have a new low-cost method to carve delicate features onto semiconductor wafers using light - and watch as it happens.

New method monitors semiconductor etching as it happens – with light

Champaign, IL | Posted on September 29th, 2012

"You can use light to image the topography and you can use light to sculpture the topography," said electrical and computer engineering professor Gabriel Popescu. "It could change the future of semiconductor etching."

Chip makers and semiconductor researchers need to very precisely control the dimensions of their devices. The dimensions of the components affect performance, speed, error rate and time to failure.

Semiconductors are commonly shaped by etching with chemicals. Etching errors, such as residual layers, can affect the ability to further process and etch as well as hamper device performance. Thus, researchers use time-consuming and costly processes to ensure precise etching - for some applications, to within a scant few nanometers.

The Illinois researchers' new technique can monitor a semiconductor's surface as it is etched, in real time, with nanometer resolution. It uses a special type of microscope that uses two beams of light to very precisely measure topography.

"The idea is that the height of the structure can be determined as the light reflects off the different surfaces," said electrical and computer engineering professor Lynford Goddard, who co-led the group with Popescu. "Looking at the change in height, you figure out the etch rate. What this allows us to do is monitor it while it's etching. It allows us to figure out the etch rate both across time and across space, because we can determine the rate at every location within the semiconductor wafer that's in our field of view."

The new method is faster, lower in cost, and less noisy than the widely used methods of atomic force microscopy or scanning tunneling microscopy, which cannot monitor etching in progress but only compare before and after measurements. In addition, the new method is purely optical, so there's no contact with the semiconductor surface and the researchers can monitor the whole wafer at once instead of point-by-point.

"I would say the main advantage of our optical technique is that it requires no contact," Popescu said. "We're just sending light, reflected off the sample, as opposed to an AFM where you need to come with a probe close to the sample."

In addition to monitoring the etching process, the light catalyzes the etching process itself, called photochemical etching. Traditional chemical etching creates features in steps or plateaus. For curved surfaces or other shapes, semiconductor researchers use photochemical etching. Usually, light shines though very expensive glass plates called masks that have distinct patterns of gray to let light through by degrees. A researcher must purchase or make a mask for each tweak of a pattern until the correct pattern of features is achieved.

By contrast, the new method uses a projector to shine a grayscale image onto the sample being etched. This allows the researchers to create complex patterns quickly and easily, and adjust them as needed.

"To create each mask is very expensive. That's impractical for research," Goddard said. "Because our technique is controlled by the computer, it can be dynamic. So you can start off etching one particular shape, midway through realize that you want to make some change, and then change the projector pattern to get the desired outcome."

The researchers envision this technology applied beyond etching, to real-time monitoring of other processes in materials science and life science - for example, watching carbon nanotubes self-assemble, or error monitoring during large-scale computer chip manufacturing. It could help chip manufacturers reduce costs and processing time by ensuring that equipment stays calibrated.

The National Science Foundation supported this work, published Sept. 28 in the journal Light: Science and Applications. Goddard and Popescu are also affiliated with the Beckman Institute for Advanced Science and Technology at the U. of I.

Graduate students Chris Edwards and Amir Arbabi were also co-authors of the paper.

####

For more information, please click here

Contacts:
Liz Ahlberg
Physical Sciences Editor
217-244-1073


Lynford Goddard
217-244-0799


To reach
Gabriel Popescu
217-333-4840

Copyright © University of Illinois at Urbana-Champaign

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 paper, “Optically Monitoring and Controlling Nanoscale Topography During Semiconductor Etching,” is available online:

Beckman Institute for Advanced Science and Technology at the U. of I.:

Related News Press

News and information

Diamonds closer to becoming ideal semiconductors: Researchers find new method for doping single crystals of diamond May 25th, 2016

Light can 'heal' defects in new solar cell materials: Defects in some new electronic materials can be removed by making ions move under illumination May 24th, 2016

Attosecond physics: A switch for light-wave electronics May 24th, 2016

Supercrystals with new architecture can enhance drug synthesis May 24th, 2016

Videos/Movies

Programmable materials find strength in molecular repetition May 23rd, 2016

Graphene makes rubber more rubbery May 23rd, 2016

ORNL demonstrates large-scale technique to produce quantum dots May 21st, 2016

Technique improves the efficacy of fuel cells: Research demonstrates a new phase transition from metal to ionic conductor May 18th, 2016

Govt.-Legislation/Regulation/Funding/Policy

Light can 'heal' defects in new solar cell materials: Defects in some new electronic materials can be removed by making ions move under illumination May 24th, 2016

Supercrystals with new architecture can enhance drug synthesis May 24th, 2016

Nanoscale Trojan horses treat inflammation May 24th, 2016

Programmable materials find strength in molecular repetition May 23rd, 2016

Chip Technology

Diamonds closer to becoming ideal semiconductors: Researchers find new method for doping single crystals of diamond May 25th, 2016

Dartmouth team creates new method to control quantum systems May 24th, 2016

Attosecond physics: A switch for light-wave electronics May 24th, 2016

Physicists create first metamaterial with rewritable magnetic ordering May 23rd, 2016

Self Assembly

Searching for a nanotech self-organizing principle May 1st, 2016

Researchers create artificial protein to control assembly of buckyballs April 27th, 2016

Brookhaven's Oleg Gang Named a Battelle 'Inventor of the Year': Recognized for work using DNA to guide and regulate the self-assembly of nanoparticles into clusters and arrays with controllable properties April 25th, 2016

Researchers develop new semiconducting polymer for forthcoming flexible electronics April 21st, 2016

Nanotubes/Buckyballs/Fullerenes

Programmable materials find strength in molecular repetition May 23rd, 2016

Nanotubes are beacons in cancer-imaging technique: Rice University researchers use spectral triangulation to pinpoint location of tumors May 21st, 2016

Unveiling the electron's motion in a carbon nanocoil: Development of a precise resistivity measurement system for quasi-one-dimensional nanomaterials using a focused ion beam May 16th, 2016

New research shows how silver could be the key to gold-standard flexible gadgets: Silver nanowires are an ideal material for current and future flexible touch-screen technologies May 13th, 2016

Discoveries

Diamonds closer to becoming ideal semiconductors: Researchers find new method for doping single crystals of diamond May 25th, 2016

Light can 'heal' defects in new solar cell materials: Defects in some new electronic materials can be removed by making ions move under illumination May 24th, 2016

Attosecond physics: A switch for light-wave electronics May 24th, 2016

Supercrystals with new architecture can enhance drug synthesis May 24th, 2016

Announcements

Diamonds closer to becoming ideal semiconductors: Researchers find new method for doping single crystals of diamond May 25th, 2016

Light can 'heal' defects in new solar cell materials: Defects in some new electronic materials can be removed by making ions move under illumination May 24th, 2016

Attosecond physics: A switch for light-wave electronics May 24th, 2016

Supercrystals with new architecture can enhance drug synthesis May 24th, 2016

Tools

Light can 'heal' defects in new solar cell materials: Defects in some new electronic materials can be removed by making ions move under illumination May 24th, 2016

More light on cancer: Scientists created nanoparticles to highlight cancer cells May 21st, 2016

Nanotubes are beacons in cancer-imaging technique: Rice University researchers use spectral triangulation to pinpoint location of tumors May 21st, 2016

Carnegie Mellon develops bio-mimicry method for preparing and labeling stem cells: Method allows researchers to prepare mesenchymal stem cells and monitor them using MRI May 19th, 2016

Industrial

Solliance realizes first up-scaled Perovskite based PV modules with 10% efficiency: Holst Centre, imec and ECN pave the road to upscaling Perovskite PV modules May 10th, 2016

First single-enzyme method to produce quantum dots revealed: Biological manufacturing process, pioneered by three Lehigh University engineers, produces equivalent quantum dots to those made chemically--but in a much greener, cheaper way May 9th, 2016

Visualizing the Lithiation of a Nanosized Iron-Oxide Material in Real Time: Electron microscopy technique reveals the reaction pathways that emerge as lithium ions are added to magnetite nanoparticles May 9th, 2016

Industrial Nanotech, Inc. Expands Distribution Network in US and Internationally May 9th, 2016

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




  Premium Products
NanoNews-Custom
Only the news you want to read!
 Learn More
NanoTech-Transfer
University Technology Transfer & Patents
 Learn More
NanoStrategies
Full-service, expert consulting
 Learn More











ASP
Nanotechnology Now Featured Books




NNN

The Hunger Project







Car Brands
Buy website traffic