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Naimo is anticipated to increase the scientific competitiveness of European Institutions and Industries.

This section is destinated to show the main scientifical breakthroughs of Naimo partners, as scientific papers already published or accepted for publication.

Published scientific articles

-to be published

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Conferences

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Patents

For a list of the patents published by NAIMO partners, click here

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36 month publishable executive summary

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In order to discuss the main achievements, draw a coherent analysis of the status of the project, and assess the level of integration, we have classified the results according to three main research lines:
a) Organic Field Effect Transistors
b) Photovoltaic and other optoelectronics devices
c) New Emerging applications

a) OFETs. The activity has been characterised by a high level of integration among materials design, fabrication and processing, device fabrication, modelling and characterisation. The charge transport properties of several materials, mainly molecules and oligomers, reported by different groups, are routinely close to the state-of-the-art mobilities (routinely 0.001-0.01 with a few examples of 0.1-1 cm2/Vs mostly in the case of single crystals and highly ordered oligomer thin films) and on-off ratios in excess of 104. These materials, although mostly p-type, can also be patterned or printed on polymers and across large areas with original fabrication approaches devised in NAIMO. Activities have now been shifted to n-type molecular semiconductors and conjugated polymers. LCs activities benefit from a good level of integration between materials design, synthesis, simulations, and different structural and spectroscopic techniques.
A wealth of unconventional fabrication methods, both serial and parallel, has been successfully applied to OFETs, with major breakthroughs especially in the case of molecules. The FET fabrication capability in NAIMO spans length scales ranging from a few tens nm up to three orders of magnitude. Several of these methods are based on joint research among NAIMO groups, as for instance, zone casting, stamp-assisted deposition, micro-contact printing and direct EBL writing of OSCs. OFET activities have prompted a substantial support from modelling at the multiscale, and from diverse SPM techniques, especially with electrical probes, XRD, photoelectron spectroscopy. The need to control environment conditions has lead to the construction of a dedicated chamber for electrical measurements of OFETs at variable T, vacuum or controlled atmosphere, and SPM. In summary, the activities in OFETs are a paradigmatic example of the fully operating potential of NAIMO.

b) Photovoltaic devices: these activities represent a considerable smaller effort in comparison with the one put on transistors. The level of integration is good between WP1, WP2, WP3 and WP6. Synthesis of materials sees a predominance of polymeric materials, (blends and copolymers), large molecules (graphenelike) and discotic LCs. The fabrication effort is mostly based on the control of the nanoscale self-organisation of polymers. Major breakthroughs have emerged for discotic LCs which may lead to a patterning of active layers in the proper orientation, or with a coupling between nanoimprinting and thin film deposition. Important contributions on the electronic structure of organic-organic interfaces have emerged from photoelectron spectroscopy; photophysics is thoroughly investigated experimentally and theoretically, and the knowledge acquired on order parameters from NMR is important.

c) New emerging applications: under this label, activities not specifically aimed to a single application or material (thus, intrinsically aimed to form a broader platform) have been classified. During the third year there has been a considerable progress in the development of new materials, dielectrics and metal clusters and nanoparticles. In particular, metal nanoparticles are used to print metals on various flexible substrates. Importantly enough, sintering temperature remains low and fully compatible with paper or plastic. A major breakthrough has occurred in device fabrication. Typically, the distance between electrodes of organic devices, i.e. OFET ~ 1-10 μm and diodes ~ 100-300 nm limits performance. Smaller distances are achievable but at the expense of easiness of fabrication. Philips has invented a novel fabrication method that allow to scale down interelectrode distance to molecular dimensions (see Nature 2006, 441, 69) paving the way to unprecedented device efficiency.