Up to now, these conductor strips have been manufactured in different production stages, but researchers at the INM – Leibniz Institute for New Materials have developed a new process with which they can create macroscopic and microscopic conductor strips in a single production step.
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).
To produce these conductor strips, the developers give a substrate a photoactive layer consisting of metal oxide nanoparticles. “We then apply a colorless UV-stable silver complex”, explains Peter William de Oliveira, Head of the Optical Materials Program Division. By exposing this series of layers to light, the silver complex on the photoactive layer is broken down and the silver ions reduced to silver. This process offers a number of advantages, including the fact that it is rapid, flexible and non-toxic.
In just one step followed by washing with water, production takes just a few minutes. Further process steps for post-treatment are not required; even heat treatment is quite unnecessary. Using this process, researchers at the INM are achieving layers up to 100 nanometers thick and a specific conductivity around a quarter of that of pure silver. Heat treatment at 120°C increases the conductivity to half that of silver.
This basic principle allows researchers at the INM to very individually apply conductor strips of different sizes to substrates such as glass or plastic. “There are three different options that we can use as required. “Writing” using a UV laser is particularly good for the first customized production and testing of a new conductor strip design, but this method is too time-consuming for mass production”, explains physicist de Oliveira.
Photomasks that are only UV-permeable at the desired positions can also be used for structuring. “The production of these masks is quite costly and has a high environmental impact. For a “semi-continuous process” they are particularly suitable for solid substrates such as glass”, says the materials expert, but they were not suitable for a potential roll-to-roll process because they are mainly composed of quartz glass and are not flexible.
The researchers are currently focusing their efforts on a third method using so-called transparent stamps. “These stamps mechanically displace the silver complex, and where there is no silver there is also no conductor strip”, in de Oliveira’s opinion. “So we can form structures measuring just a few micrometers. Since the stamps are made of a flexible polymer, we have here the possibility of arranging them on a roll. Because they are transparent, we are working on incorporating the UV source in the roll, so the first steps would be done for a roll-to-roll process”, the Head of the Program Division sums up. This has enabled conductor strip structures of different sizes to be produced on substrates such as polyethylene or polycarbonate film on a large scale.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.
Atomic structure of ultrasound material not what anyone expected
21.02.2018 | North Carolina State University
Hidden talents: Converting heat into electricity with pencil and paper
20.02.2018 | Helmholtz-Zentrum Berlin für Materialien und Energie
Quantum computers may one day solve algorithmic problems which even the biggest supercomputers today can’t manage. But how do you test a quantum computer to...
For the first time, a team of researchers at the Max-Planck Institute (MPI) for Polymer Research in Mainz, Germany, has succeeded in making an integrated circuit (IC) from just a monolayer of a semiconducting polymer via a bottom-up, self-assembly approach.
In the self-assembly process, the semiconducting polymer arranges itself into an ordered monolayer in a transistor. The transistors are binary switches used...
Breakthrough provides a new concept of the design of molecular motors, sensors and electricity generators at nanoscale
Researchers from the Institute of Organic Chemistry and Biochemistry of the CAS (IOCB Prague), Institute of Physics of the CAS (IP CAS) and Palacký University...
For photographers and scientists, lenses are lifesavers. They reflect and refract light, making possible the imaging systems that drive discovery through the microscope and preserve history through cameras.
But today's glass-based lenses are bulky and resist miniaturization. Next-generation technologies, such as ultrathin cameras or tiny microscopes, require...
Scientists from the University of Zurich have succeeded for the first time in tracking individual stem cells and their neuronal progeny over months within the intact adult brain. This study sheds light on how new neurons are produced throughout life.
The generation of new nerve cells was once thought to taper off at the end of embryonic development. However, recent research has shown that the adult brain...
15.02.2018 | Event News
13.02.2018 | Event News
12.02.2018 | Event News
22.02.2018 | Life Sciences
22.02.2018 | Physics and Astronomy
22.02.2018 | Earth Sciences