IDTechEx attended the International Conference on Organic Electronics 2007 in Eindhoven this month. With 33 papers, 28 posters, and speakers and attendees from all over the world, this three and a half day conference was focused on recent results in the research of organic materials for electronic devices.
Most of the papers and posters came from universities and research institutes. Companies presenting included PolyIC, Merck, Dow Chemical, Neotech, Optomec, and Philips.
Many papers dealed with basic research in materials and processes. Some papers including the first invited talk covered theoretical aspects of conductivity in organic materials. One of the main statements was to learn more from models successfully used in the past to describe similar phenomenons in inorganic matter.
Dow Corning presented a material that improves the Nanoimprint lithography (NIL) towards higher throughput, better reproducibility, and more materials/substrates choice. The idea was to use a UV-curable resist based on cationic polymerization of silicone epoxies. They showed 20nm trenches produced with this material. Another material presented was a thermal curable polydimethylsiloxane based resist used to produce 70nm lines at above 80ºC within a few seconds. Both developments are important for the wider use of NIL in making small devices on an industrial scale.
A group from the Faculty of Electronic Engineering of the Czech Technical University in Prague presented an interesting approach to self-powered microsystems. Instead of using batteries, they propose to incorporate a micro generator, based on a serpentine cantilever field of PVDF, a piezoelectric material. As long as the device is in motion, energy could be gained by distortion of the structure and resulting voltage. In combination with a component to store electrical energy this could be an interesting alternative to conventional energy supplies, based on the conversion of mechanical to electrical energy.
The Holst Centre/ TNO Eindhoven gave a presentation on inkjet printed organic photodiodes for sensor applications. While organic photosensitive materials are mainly investigated with respect to use in photovoltaics, they are also allowed to build flexible image sensors. Large area deposition techniques as spin-coating are not suitable since a sensor device will require single dots - here the inkjet technology seems to offer the right approach, allowing putting down the material in small dots in whatever patterns desired. Functional photodiode arrays of 100 pixels, 2x2 mm, without a well were demonstrated.
The speech by PolyIC revealed some aspects (and difficulties) of making a printed ID tag. Still, the voltage needed to run a 13.56MHz transponder is in the range of 14V, so the requirements for the rectifier are pretty high. First results presented were obtained with a hybrid transponder setup, meaning all main functions of the transponder were realized by separate polymer devices mounted to an etched copper
antenna. From the discussion it was understood the ID tag announced for Fall 2007 will be 4bit and organic transponder on copper.
Most of the other papers dealt with research in a quite early stage, some just to better understand models describing charge behaviour in organic semiconductors with no immediate relevance to industrial applications.
Details of the event can be seen at http://www.extra.research.philips.com/icoe/2007/index.htm
Source of top image: www.physorg.com