Nanotechnology Now

Our NanoNews Digest Sponsors



Heifer International

Wikipedia Affiliate Button


android tablet pc

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

Iranian Experts Clean Uranium-Contaminated Water by Nano-Particles November 23rd, 2014

Novel Method Found for Connection of Metallic Alloys to Polymers November 23rd, 2014

New research project supports internationalisation in nano-research: Launch of new “Baltic Sea Network” November 22nd, 2014

3rd Iran-Proposed Nano Standard Approved by International Standard Organization November 22nd, 2014

Flexible Electronics

Canatu Launches CNB In-Mold Film for Transparent Touch on 3D Surfaces –in Cars, Household Appliances, Wearables, Portables November 20th, 2014

New way to move atomically thin semiconductors for use in flexible devices November 13th, 2014

Imaging

Leica Microsystems Presents Universal Hybrid Detector for Single Molecule Detection and Imaging at SfN and ASCB: Leica HyD SMD - the Optimal Detector for Precise and Reliable SMD data November 20th, 2014

NRL Scientists Discover Novel Metamaterial Properties within Hexagonal Boron Nitride November 20th, 2014

Spectral Surface Mapping with Microscopic Resolution: CRAIC Technologies introduces Spectral Surface Mapping™ (S2M™) software November 18th, 2014

Two sensors in one: Nanoparticles that enable both MRI and fluorescent imaging could monitor cancer, other diseases November 18th, 2014

Thin films

New way to move atomically thin semiconductors for use in flexible devices November 13th, 2014

Graphene Frontiers Partners with Madico to Accelerate Material Production: Deal to ignite and fulfill demand for industrial scale graphene film that supports energy, consumer electronics, membranes/filtration, solar and other applications November 12th, 2014

New materials for more powerful solar cells: Major breakthrough in solar energy November 11th, 2014

Govt.-Legislation/Regulation/Funding/Policy

New research project supports internationalisation in nano-research: Launch of new “Baltic Sea Network” November 22nd, 2014

3rd Iran-Proposed Nano Standard Approved by International Standard Organization November 22nd, 2014

NMTI announces breakthrough solutions for HAMR nanoantenna for next-generation ultra-high density magnetic storage November 21st, 2014

Quantum mechanical calculations reveal the hidden states of enzyme active sites November 20th, 2014

Chip Technology

Nanometrics Announces Upcoming Investor Events November 19th, 2014

A novel method for identifying the body’s ‘noisiest’ networks November 19th, 2014

Researchers create & control spin waves, lifting prospects for enhanced info processing November 17th, 2014

VDMA Electronics Production Equipment: Growth track for 2014 and 2015 confirmed: Business climate survey shows robust industry sector November 14th, 2014

Self Assembly

Live Images from the Nano-cosmos: Researchers watch layers of football molecules grow November 5th, 2014

Outsmarting Thermodynamics in Self-assembly of Nanostructures: Berkeley Lab reports method for symmetry-breaking in feedback-driven self-assembly of optical metamaterials November 4th, 2014

NYU Researchers Break Nano Barrier to Engineer the First Protein Microfiber October 23rd, 2014

NIST offers electronics industry 2 ways to snoop on self-organizing molecules October 22nd, 2014

Announcements

Iranian Experts Clean Uranium-Contaminated Water by Nano-Particles November 23rd, 2014

Novel Method Found for Connection of Metallic Alloys to Polymers November 23rd, 2014

New research project supports internationalisation in nano-research: Launch of new “Baltic Sea Network” November 22nd, 2014

3rd Iran-Proposed Nano Standard Approved by International Standard Organization November 22nd, 2014

Tools

Iranian Experts Clean Uranium-Contaminated Water by Nano-Particles November 23rd, 2014

Leica Microsystems Presents Universal Hybrid Detector for Single Molecule Detection and Imaging at SfN and ASCB: Leica HyD SMD - the Optimal Detector for Precise and Reliable SMD data November 20th, 2014

Nanometrics Announces Upcoming Investor Events November 19th, 2014

Two sensors in one: Nanoparticles that enable both MRI and fluorescent imaging could monitor cancer, other diseases November 18th, 2014

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







© Copyright 1999-2014 7th Wave, Inc. All Rights Reserved PRIVACY POLICY :: CONTACT US :: STATS :: SITE MAP :: ADVERTISE