The research scientists at INM - Leibniz Institute for New Materials are presenting a new process that, in a single step, allows manufacture of conductive paths that are just a few micrometers in width on flexible foils. As a result, new designs for appliances with flexible or even rollable displays will be possible.
In order for touchscreens on smartphones and tablets to function, microscopically fine conductor paths are required on their surfaces. When the users' fingers tip on or wipe over them, electrical circuits open and close, thus making the different functions of the smartphone possible.
At the edges of the appliances, these microscopic circuit paths come together to form larger conductive paths. Until now, these different conductive paths had to be manufactured in several steps in time-consuming processes.
The research scientists at INM – Leibniz-Institute for New Materials are now presenting a new process that, in a single step, allows manufacture of conductive paths that are just a few micrometers in width on carrier materials such as glass but also on flexible foils.
On plastic foil, in particular, manufacture using the roll-to-roll process thus becomes particularly efficient. As a result, new designs for appliances with flexible or even rollable displays will be possible.
The researchers will be presenting their results from 25 to 29 April 2016 in Hall 2 at the stand B46 of the Hannover Messe in the context of the leading trade fair for R & D and Technology Transfer.
For the new process, the developers use a process known as photochemical metallization: When a photoactive layer is irradiated by UV light, colorless silver compounds are transformed into electrically conductive metallic silver. Several methods can be applied to transfer the silver compound in paths or other structures on plastic foil or glass. In this way, paths of varying sizes down to the smallest size of a thousandth of a millimeter can be achieved. By irradiating these with UV light, corresponding conductive paths are created.
“First, the foils are coated with a photoactive layer of metal oxide nanoparticles,” Peter William de Oliveira, Head of Optical Materials explained. “After that we apply the colorless, UV-stable silver compound.” By irradiation of this sequence of layers, the silver compound disintegrates on the photoactive layer and the silver ions are reduced to form metallic, electrically conductive silver.
Oliviera added that this process offered several benefits: Since it is fast, flexible, variable in size, inexpensive and environmentally friendly, further process steps for post-treatment became unnecessary.
This basic principle allows conductive paths to be created very individually. “There are three different possibilities we can use depending on the requirements: `Writing conductive paths` using UV lasers is the process which is particularly suitable for the initial customized prototype manufacture and testing the new design of the conductive path. However, for mass production, this method is too time-consuming,” the physicist de Oliveira explained.
Photomasks that are only permeable for UV light at the desired positions can also be used for structuring. “For a `semi-continuous process` they are particularly suitable for applying the conductive paths on glass,” the materials expert says.
The researchers are currently working intensely on a third method, the usage of transparent stamps. “These stamps push out the silver compound mechanically; conductive paths then only occur where there is still silver compound,” de Oliveira stated. Since the stamps are made of a soft plastic, they can be arranged on a roll. Because they are transparent, researchers at INM are now working on embedding the UV source directly in the roll.
“Thus, the initial steps for a roll-to-roll process would already have been taken,” the Head of Optical Materials group concluded. It would therefore be possible to manufacture conductive path structures of various sizes on foils on a large scale.
Your contact at the Booth:
Dr. Michael Opsölder
Your expert at INM:
Dr. Peter William de Oliveira
INM – Leibniz Institute for New Materials
Head Optical Materials
Head InnovationCenter INM
INM conducts research and development to create new materials – for today, tomorrow and beyond. Chemists, physicists, biologists, materials scientists and engineers team up to focus on these essential questions: Which material properties are new, how can they be investigated and how can they be tailored for industrial applications in the future? Four research thrusts determine the current developments at INM: New materials for energy application, new concepts for medical surfaces, new surface materials for tribological systems and nano safety and nano bio. Research at INM is performed in three fields: Nanocomposite Technology, Interface Materials, and Bio Interfaces.
INM – Leibniz Institute for New Materials, situated in Saarbrücken, is an internationally leading centre for materials research. It is an institute of the Leibniz Association and has about 220 employees.
Dr. Carola Jung | idw - Informationsdienst Wissenschaft
Innovative Infrared Emitters Optimize the Manufacture of Vehicle Interior Fittings Using Vacuum Lamination
01.08.2017 | Heraeus Noblelight GmbH
Bug-proof communication with entangled photons
22.06.2017 | Fraunhofer-Gesellschaft
Whether you call it effervescent, fizzy, or sparkling, carbonated water is making a comeback as a beverage. Aside from quenching thirst, researchers at the University of Illinois at Urbana-Champaign have discovered a new use for these "bubbly" concoctions that will have major impact on the manufacturer of the world's thinnest, flattest, and one most useful materials -- graphene.
As graphene's popularity grows as an advanced "wonder" material, the speed and quality at which it can be manufactured will be paramount. With that in mind,...
Physicists at the University of Bonn have managed to create optical hollows and more complex patterns into which the light of a Bose-Einstein condensate flows. The creation of such highly low-loss structures for light is a prerequisite for complex light circuits, such as for quantum information processing for a new generation of computers. The researchers are now presenting their results in the journal Nature Photonics.
Light particles (photons) occur as tiny, indivisible portions. Many thousands of these light portions can be merged to form a single super-photon if they are...
For the first time, scientists have shown that circular RNA is linked to brain function. When a RNA molecule called Cdr1as was deleted from the genome of mice, the animals had problems filtering out unnecessary information – like patients suffering from neuropsychiatric disorders.
While hundreds of circular RNAs (circRNAs) are abundant in mammalian brains, one big question has remained unanswered: What are they actually good for? In the...
An experimental small satellite has successfully collected and delivered data on a key measurement for predicting changes in Earth's climate.
The Radiometer Assessment using Vertically Aligned Nanotubes (RAVAN) CubeSat was launched into low-Earth orbit on Nov. 11, 2016, in order to test new...
A study led by scientists of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science in Hamburg presents evidence of the coexistence of superconductivity and “charge-density-waves” in compounds of the poorly-studied family of bismuthates. This observation opens up new perspectives for a deeper understanding of the phenomenon of high-temperature superconductivity, a topic which is at the core of condensed matter research since more than 30 years. The paper by Nicoletti et al has been published in the PNAS.
Since the beginning of the 20th century, superconductivity had been observed in some metals at temperatures only a few degrees above the absolute zero (minus...
16.08.2017 | Event News
04.08.2017 | Event News
26.07.2017 | Event News
18.08.2017 | Life Sciences
18.08.2017 | Physics and Astronomy
18.08.2017 | Materials Sciences