Nanotechnology Now

Our NanoNews Digest Sponsors

Heifer International

Wikipedia Affiliate Button


DHgate

Home > Press > CHESS X-rays help characterize organic transistors

Advanced Materials
The cover image shows the X-ray microbeam footprint on the gate electrode of an organic transistor and scattered X-ray beams emanating from the molecular film.
Advanced Materials

The cover image shows the X-ray microbeam footprint on the gate electrode of an organic transistor and scattered X-ray beams emanating from the molecular film.

Abstract:
Plastic electronics, in which an organic material replaces silicon, hold promise for low-cost, flexible electronics. But understanding and controlling these materials' microstructures is an ongoing challenge.

CHESS X-rays help characterize organic transistors

Ithaca, NY | Posted on November 20th, 2012

With the help of the D1 X-ray beamline at the Cornell High Energy Synchrotron Source (CHESS), scientists have come many steps closer to designing the perfect organic semiconductor by spatially mapping the microstructure, texture, grain sizes and grain orientations of organic semiconductor thin films.

Detlef Smilgies, senior research associate at CHESS, is co-author of an article in the Nov. 2 issue of the journal Advanced Materials (Vol. 24, No. 41), featured on the journal's cover, that describes this direct structural mapping.

The study's senior author, Aram Amassian of King Abdullah University of Science and Technology (KAUST), is a former Cornell postdoctoral associate, and the first author, Amassian's research associate Ruipeng Li, is a former visiting graduate student at CHESS; both are frequent Cornell synchrotron users.

The performance of a transistor is usually described by the mobility of its charge carriers -- the quicker the charge carriers can move through the material, the better. Charge mobility can be hampered by grain boundaries, which are the interfaces of individual grains in a crystal, either because they are misaligned or growing on different planes.

These interfaces play an important role in the texture of the crystalline organic material. A basic transistor typically has a source, where charge carriers enter; a drain, where the charge carriers exit; and a gate in the middle, which regulates the mobility of the charge carriers. In the most common architecture, the organic semiconductor is printed on a substrate pre-patterned with source and drain electrodes. The organic layer can thus form different growth planes on different parts of the substrate, and it's hard to tell fundamentally which growth planes are best to carry charges.

To shed some light on this question, the researchers used a technique called microbeam grazing incidence wide-angle X-ray scattering to probe how the organic transistor's molecular structure changed within the gate channel of the transistor, i.e., between the source and the drain electrodes. The microbeam at CHESS D1 station was obtained with an X-ray-focusing capillary -- an optical device that helps narrow the X-ray beam -- only 10 microns wide or one-fifth the width of a human hair.

This microbeam intercepted the transistors at a low angle of 2 degrees; the resulting wide-angle scattered X-rays were collected with a high-resolution camera. The scientists found that a particular growth plane that formed on the gold electrode extended up to tens of microns into the channel. Then a mix of planes occurred in the center of the channel.

When the channel width was below 20 microns, a favorable orientation prevailed, and the devices had good performance, while wider channels with mixed structures performed more poorly, with lower carrier mobility.

A chemical modification of the electrode surfaces with a fluorinated self-assembled monolayer was found to promote the formation of the favorable growth plane, which extended well into the channel. In some cases this growth plane bridged the channel entirely, significantly reducing the bottlenecks to charge transport of the untreated device.

Smilgies developed the instrumentation used in the experiment and helped with calibration and characterization of the microbeam used in the study. D1, he noted, is especially suited for in-situ studies of soft materials -- techniques that Smilgies has developed over the past 12 years at CHESS.

Oana Jurchescu and her student Jeremy Ward at Wake Forest University supplied the devices; John Anthony and Marcia Payne at the University of Kentucky provided the molecular material. CHESS is supported by the National Science Foundation and National Institutes of Health. The study was also supported by the KAUST Office of Competitive Research Funds, which funds part of the D1 beamline instrumentation.

####

For more information, please click here

Contacts:
Media Contact:
Syl Kacapyr
(607) 255-7701


Cornell Chronicle:
Anne Ju
(607) 255-9735

Copyright © Cornell University

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 News Press

News and information

Chemical cages: New technique advances synthetic biology February 10th, 2016

New thin film transistor may lead to flexible devices: Researchers engineer an electronics first, opening door to flexible electronics February 10th, 2016

Making sense of metallic glass February 9th, 2016

Electron's 1-D metallic surface state observed: A step for the prediction of electronic properties of extremely-fine metal nanowires in next-generation semiconductors February 9th, 2016

Nanoparticle therapy that uses LDL and fish oil kills liver cancer cells February 9th, 2016

Flexible Electronics

New thin film transistor may lead to flexible devices: Researchers engineer an electronics first, opening door to flexible electronics February 10th, 2016

Thin films

New thin film transistor may lead to flexible devices: Researchers engineer an electronics first, opening door to flexible electronics February 10th, 2016

Imaging

Making sense of metallic glass February 9th, 2016

Chiral magnetic effect generates quantum current: Separating left- and right-handed particles in a semi-metallic material produces anomalously high conductivity February 8th, 2016

Govt.-Legislation/Regulation/Funding/Policy

New thin film transistor may lead to flexible devices: Researchers engineer an electronics first, opening door to flexible electronics February 10th, 2016

SUNY Poly and GLOBALFOUNDRIES Announce New $500M R&D Program in Albany To Accelerate Next Generation Chip Technology: Arrival of Second Cutting Edge EUV Lithography Tool Launches New Patterning Center That Will Generate Over 100 New High Tech Jobs at SUNY Poly February 9th, 2016

Making sense of metallic glass February 9th, 2016

Nanoparticle therapy that uses LDL and fish oil kills liver cancer cells February 9th, 2016

Chip Technology

New thin film transistor may lead to flexible devices: Researchers engineer an electronics first, opening door to flexible electronics February 10th, 2016

SUNY Poly and GLOBALFOUNDRIES Announce New $500M R&D Program in Albany To Accelerate Next Generation Chip Technology: Arrival of Second Cutting Edge EUV Lithography Tool Launches New Patterning Center That Will Generate Over 100 New High Tech Jobs at SUNY Poly February 9th, 2016

Electron's 1-D metallic surface state observed: A step for the prediction of electronic properties of extremely-fine metal nanowires in next-generation semiconductors February 9th, 2016

Metal oxide sandwiches: New option to manipulate properties of interfaces February 8th, 2016

Self Assembly

New type of nanowires, built with natural gas heating: UNIST research team developed a new simple nanowire manufacturing technique February 1st, 2016

Researchers develop completely new kind of polymer: Hybrid polymers could lead to new concepts in self-repairing materials, drug delivery and artificial muscles January 30th, 2016

Polymer nanowires that assemble in perpendicular layers could offer route to tinier chip components January 23rd, 2016

Nanodevice, build thyself: Researchers in Germany studied how a multitude of electronic interactions govern the encounter between a molecule called porphine and copper and silver surfaces January 18th, 2016

Announcements

Chemical cages: New technique advances synthetic biology February 10th, 2016

New thin film transistor may lead to flexible devices: Researchers engineer an electronics first, opening door to flexible electronics February 10th, 2016

Superconductivity: Footballs with no resistance - Indications of light-induced lossless electricity transmission in fullerenes contribute to the search for superconducting materials for practical applications February 9th, 2016

SUNY Poly and GLOBALFOUNDRIES Announce New $500M R&D Program in Albany To Accelerate Next Generation Chip Technology: Arrival of Second Cutting Edge EUV Lithography Tool Launches New Patterning Center That Will Generate Over 100 New High Tech Jobs at SUNY Poly February 9th, 2016

Tools

Making sense of metallic glass February 9th, 2016

Chiral magnetic effect generates quantum current: Separating left- and right-handed particles in a semi-metallic material produces anomalously high conductivity February 8th, 2016

Metal oxide sandwiches: New option to manipulate properties of interfaces February 8th, 2016

Researchers discover new phase of boron nitride and a new way to create pure c-BN February 5th, 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