Nanotechnology Now

Our NanoNews Digest Sponsors


Heifer International

Wikipedia Affiliate Button

Home > Press > Thermochemical nanopatterning of organic semiconductors

Figure – A schematic of the Wollaston wire probe and the lithographic process (bottom). a Regular patterns drawn over large areas using scanning thermochemical lithography. The top image is an atomic force micrograph, whilst the bottom image is from a confocal microscope. b Atomic force microscope image of a high resolution lithographic line (top) and its cross-section (bottom).
Figure – A schematic of the Wollaston wire probe and the lithographic process (bottom). a Regular patterns drawn over large areas using scanning thermochemical lithography. The top image is an atomic force micrograph, whilst the bottom image is from a confocal microscope. b Atomic force microscope image of a high resolution lithographic line (top) and its cross-section (bottom).

Abstract:
Researchers from the London Centre for Nanotechnology (LCN) and University College London (UCL) have fabricated sub-30 nm luminescent features of an organic semiconductor via spatially selective conversion and patterning of its precursor by using a heatable, micron-size scanning probe (see figure below). The results will soon be reported in the journal Nature Nanotechnology.

Thermochemical nanopatterning of organic semiconductors

London | Posted on September 8th, 2009

The future development of electronics and photonics relies on a range of sophisticated lithographyic techniques for the patterning of semiconducting, dielectric, and metallic materials. Researchers at the London Centre of Nanotechnology (LCN), the Department of Physics and Astronomy, and the Eastman Dental Institute at UCL, have now developed a thermochemical patterning technique for materials known as organic semiconductors.

These materials can be used in light-emitting diodes (LEDs), solar cells, lasers and transistors, and their potential is in low processing costs and the ability to build devices on flexible substrates. However, applications of these materials in nanoelectronics and nanophotonics are limited by the range of patterning techniques available. Many of the approaches to nanolithography that are used to pattern inorganic materials, such as e-beams or Focused Ion Beams (FIBs), are too harsh for organic semiconductors, that can be damaged by the high energy of the patterning beams, or by the chemicals needed for the processing.

So, instead of using standard optical or other "conventional" high-resolution lithographies, the UCL researchers used a small heat source for the patterning. This heat source, known as a modified Wollaston wire, can be mounted on an atomic force microscope and scanned across surfaces to chemically convert all areas it comes into contact with. This technique has allowed the UCL researchers to achieve patterned resolutions below 28 nm and write speeds of 100 µm/s in the widely used organic semiconductor, PPV. The result is particularly surprising given the large diameter of the heat source (5 µm) compared to the resolutions achieved, and since it is likely that resolution could be further improved with the use of nanoscale heat sources, as already reported by other groups.

There has already been some commercial interest in using atomic force microscopes to pattern surfaces, as for example by IBM in their ‘millipede' project, that was aimed at data-storage applications, but such a thermochemical approach opens up new possibilities. In particular, this work shows that thermochemical lithography offers a versatile, simple and reliable nanopatterning technique. For example, thermo-crosslinkable additives could easily be added to a variety of other solution-processible semiconductors. The technique should also be generally applicable to other classes of materials. A large number of optical materials, including many commercial cross-linker additives and photoresists, rely in fact on chemical mechanisms that can also be thermally activated.

The group, led by Franco Cacialli, has previously used scanning near-field optical lithography (SNOL) for nanopatterning of PPV structures from the same precursor polymer, poly(p-xylene tetrahydrothiophenium chloride) (PXT). This work included the fabrication of quasi-periodic two-dimensional structures with potential for photonic applications. However, the thermochemical technique now developed (Scanning Thermal lithography, or SThL) enables one to bypass the UV insolubilisation step, and the complications and additional costs imposed by the needs for lasers, optics, and sophisticated optical fibre probes.

More details regarding the research in the Organic Semiconductors Group led by Franco Cacialli can be found at the website: www.cmmp.ucl.ac.uk/~fc/OS/

####

About London Centre for Nanotechnology (LCN)
The London Centre for Nanotechnology, LCN, is a UK based multidisciplinary enterprise operating at the forefront of science and technology. It is a joint venture between University College London and Imperial College London and is based at the Bloomsbury and South Kensington sites. It has a unique operating model that accesses and focusses the combined skills of the departments of chemistry, physics, materials, medicine, electrical and electronic engineering, mechanical engineering, chemical engineering, biochemical engineering and earth sciences across the two universities.

For more information, please click here

Contacts:
Bloomsbury (UCL) Site
London Centre for Nanotechnology
17-19 Gordon Street
London WC1H 0AH
tel: +44 (0)20 7679 0604
fax: +44 (0)20 7679 0595

Copyright © London Centre for Nanotechnology (LCN)

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

An accelerated pipeline to open materials research: ORNL workflow system unites imaging, algorithms, and HPC to advance materials discovery and design July 24th, 2016

Russian physicists discover a new approach for building quantum computers: Physicists find a way of 'bundling together' multiple elements of a quantum computer July 24th, 2016

A 'smart dress' for oil-degrading bacteria July 24th, 2016

New superconducting coil improves MRI performance: UH-led research offers higher resolution, shorter scan time July 23rd, 2016

Display technology/LEDs/SS Lighting/OLEDs

Researchers develop faster, precise silica coating process for quantum dot nanorods July 12th, 2016

Integrated trio of 2-D nanomaterials unlocks graphene electronics applications: Voltage-controlled oscillator developed at UC Riverside could be used in thousands of applications from computers to wearable technologies July 7th, 2016

GraphExeter illuminates bright new future for flexible lighting devices June 23rd, 2016

New nanomaterial offers promise in bendable, wearable electronic devices: Electroplated polymer makes transparent, highly conductive, ultrathin film June 13th, 2016

Chip Technology

An accelerated pipeline to open materials research: ORNL workflow system unites imaging, algorithms, and HPC to advance materials discovery and design July 24th, 2016

Russian physicists discover a new approach for building quantum computers: Physicists find a way of 'bundling together' multiple elements of a quantum computer July 24th, 2016

Quantum drag:University of Iowa physicist says current in one iron magnetic sheet can create quantized spin waves in another, separate sheet July 22nd, 2016

New Yale-developed device lengthens the life of quantum information July 22nd, 2016

Nanoelectronics

Quantum drag:University of Iowa physicist says current in one iron magnetic sheet can create quantized spin waves in another, separate sheet July 22nd, 2016

Scientists glimpse inner workings of atomically thin transistors July 21st, 2016

'Green' electronic materials produced with synthetic biology July 16th, 2016

Tiny works of art with great potential: New materials for the construction of metal-organic 2-dimensional quasicrystals July 15th, 2016

Announcements

An accelerated pipeline to open materials research: ORNL workflow system unites imaging, algorithms, and HPC to advance materials discovery and design July 24th, 2016

Russian physicists discover a new approach for building quantum computers: Physicists find a way of 'bundling together' multiple elements of a quantum computer July 24th, 2016

A 'smart dress' for oil-degrading bacteria July 24th, 2016

New superconducting coil improves MRI performance: UH-led research offers higher resolution, shorter scan time July 23rd, 2016

Tools

An accelerated pipeline to open materials research: ORNL workflow system unites imaging, algorithms, and HPC to advance materials discovery and design July 24th, 2016

New superconducting coil improves MRI performance: UH-led research offers higher resolution, shorter scan time July 23rd, 2016

The birth of quantum holography: Making holograms of single light particles! July 21st, 2016

A mini-antenna for the data processing of tomorrow: Nature Nanotechnology: Short-wavelength spin waves generated directly for the first time July 20th, 2016

Photonics/Optics/Lasers

RMIT researchers make leap in measuring quantum states July 21st, 2016

The birth of quantum holography: Making holograms of single light particles! July 21st, 2016

Graphene photodetectors: Thinking outside the 2-D box July 21st, 2016

Scientists develop way to upsize nanostructures into light, flexible 3-D printed materials: Virginia Tech, Livermore National Lab researchers develop hierarchical 3-D printed metallic materials July 20th, 2016

Solar/Photovoltaic

An accelerated pipeline to open materials research: ORNL workflow system unites imaging, algorithms, and HPC to advance materials discovery and design July 24th, 2016

Researchers discover key mechanism for producing solar cells: Better understanding of perovskite solar cells could boost widespread use July 21st, 2016

The future of perovskite solar cells has just got brighter -- come rain or shine: Korean researchers at POSTECH have succeeded in developing high-efficiency perovskite solar cells that retain excellent performance over two months in a very humid condition July 21st, 2016

Scientists develop way to upsize nanostructures into light, flexible 3-D printed materials: Virginia Tech, Livermore National Lab researchers develop hierarchical 3-D printed metallic materials July 20th, 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