TCOs are normally produced on solid substrates using vacuum coating such as sputtering, but can also be applied to flexible substrates such as plastic film using special TCO inks.
Transparent conducting oxides (TCO) are widely used as transparent electrodes.
Source: Uwe Bellhäuser
To do this, developers at the INM use TCO inks containing TCO nanoparticles and produced using wet chemistry processes. This method enables not only application to plastics and films but also, for the first time, direct printing of transparent conductor structures.
The INM will be exhibiting these and other developments from 15 to 17 October at Materialica 2013 in Munich and from 23 to 24 October at Eurofinish 2013 in Ghent (Belgium).
“We produce special nanoparticles from the transparent conducting oxides”, explains Peter William de Oliveira, Head of the Optical Materials Program Division. “By adding a solvent and a special binder, these modified TCO nanoparticles can be applied to the film directly by gravure printing as an “ink” using a printing plate”, he adds.
This process has a number of advantages. Gravure printing enables TCO layers to be printed cost-effectively in just one process step. As a result of UV curing at temperatures below 150°C, it is also possible to coat thin plastic films. The binder fulfills a number of tasks here. It produces good adhesion of the TCO nanoparticles to the substrate and also increases the flexibility of the TCO layers. This means that the conductivity remains the same, even if the films become distorted - a clear advantage over current high-vacuum techniques such as sputtering. “There is still potential here for further development”, explains physicist de Oliveira. “If we succeed in also making the binder conductive, conductivity as a whole will increase and the surface resistance will be further reduced.”
Coating on flexible film substrates is possible using the classic roll-to-roll process. Initial experiments on this at the INM are promising, and researchers are agreed that the use of structured rolls in future will mean that large, structured, conductive surfaces can also be printed cost-effectively and with a high output.
With vacuum coating processes such as the sputter method, expensive high-vacuum apparatus and large TCO targets are needed for coating large areas; there is also the limited possibility of evenly coating curved substrates using this technique.
At the INM, too, the material of choice is predominantly indium tin oxide (ITO). Because of dwindling resources and the high price of the raw material indium, researchers at the INM are also increasingly testing alternative transparent oxides such as aluminum zinc oxide (AZO).Contact:
INM – Leibniz Institute for New Materials, situated in Saarbruecken, is an internationally leading centre for materials research. It is an institute of the Leibniz Association and has about 190 employees.
AchemAsia 2019 will take place in Shanghai
15.06.2018 | DECHEMA Gesellschaft für Chemische Technik und Biotechnologie e.V.
Insects supply chitin as a raw material for the textile industry
05.06.2018 | Fraunhofer-Institut für Grenzflächen- und Bioverfahrenstechnik IGB
For the first time ever, scientists have determined the cosmic origin of highest-energy neutrinos. A research group led by IceCube scientist Elisa Resconi, spokesperson of the Collaborative Research Center SFB1258 at the Technical University of Munich (TUM), provides an important piece of evidence that the particles detected by the IceCube neutrino telescope at the South Pole originate from a galaxy four billion light-years away from Earth.
To rule out other origins with certainty, the team led by neutrino physicist Elisa Resconi from the Technical University of Munich and multi-wavelength...
For the first time a team of researchers have discovered two different phases of magnetic skyrmions in a single material. Physicists of the Technical Universities of Munich and Dresden and the University of Cologne can now better study and understand the properties of these magnetic structures, which are important for both basic research and applications.
Whirlpools are an everyday experience in a bath tub: When the water is drained a circular vortex is formed. Typically, such whirls are rather stable. Similar...
Physicists working with Roland Wester at the University of Innsbruck have investigated if and how chemical reactions can be influenced by targeted vibrational excitation of the reactants. They were able to demonstrate that excitation with a laser beam does not affect the efficiency of a chemical exchange reaction and that the excited molecular group acts only as a spectator in the reaction.
A frequently used reaction in organic chemistry is nucleophilic substitution. It plays, for example, an important role in in the synthesis of new chemical...
Optical spectroscopy allows investigating the energy structure and dynamic properties of complex quantum systems. Researchers from the University of Würzburg present two new approaches of coherent two-dimensional spectroscopy.
"Put an excitation into the system and observe how it evolves." According to physicist Professor Tobias Brixner, this is the credo of optical spectroscopy....
Ultra-short, high-intensity X-ray flashes open the door to the foundations of chemical reactions. Free-electron lasers generate these kinds of pulses, but there is a catch: the pulses vary in duration and energy. An international research team has now presented a solution: Using a ring of 16 detectors and a circularly polarized laser beam, they can determine both factors with attosecond accuracy.
Free-electron lasers (FELs) generate extremely short and intense X-ray flashes. Researchers can use these flashes to resolve structures with diameters on the...
13.07.2018 | Event News
12.07.2018 | Event News
03.07.2018 | Event News
17.07.2018 | Information Technology
17.07.2018 | Materials Sciences
17.07.2018 | Power and Electrical Engineering