High-frequency printed and direct-written Organic-hybrid Integrated Circuits
The HEROIC project aims at filling the gap between the currently low operation frequencies of printed, organic flexible electronics and the high-frequency regime, by demonstrating polymer-based field-effect transistors with maximum operation frequencies of 1 GHz and complementary integrated logic circuits switching in the 10-100 MHz range, fabricated by means of printing and direct-writing scalable processes in order to retain low temperature manufacturability of cost-effective large area electronics on plastic. The recent development of semiconducting polymers with mobilities in the range of 1 to 10 cm2/Vs, and even higher in the case of aligned films, suggests that suitably downscaled printed polymer transistors with operation frequencies in the GHz regime, at least three orders of magnitude higher than current printed polymer devices, are achievable, by addressing in a holistic approach the specific challenges set in the HEROIC trans-disciplinary research programme: (i)development of scalable high resolution processes for the patterning of functional inks, where printing will be combined with direct-writing techniques such as fs-laser machining, both in an additive and subtractive approach; (ii)development of printable nanoscale hybrid dielectrics with high specific capacitance, where low-k polymer buffer materials will be combined with solution processable high-k dielectrics, such as insulating metal oxides; (iii)improvement of the control of charge injection and transport in printed polymer and hybrid semiconductors, where high-mobility 1-D and 2-D structures are included in polymer films; (iv)development of advanced printed and direct-written transistors architectures with low parasitic capacitances for high-speed operation. HEROIC will radically advance and expand the applicability of polymer-based printed electronics, thus making it suitable for next generation portable and wearable short-range wireless communicating devices with low power consumption.
Inkjet-Printed organic Photodetectors for Imaging Applications
Marie-Curie Career Integration Grant 2011
Grant agreement PCIG09-GA-2011–291844, within European Union Seventh Framework Programme (FP7/2007–2013)
The recent development of a wide range of solution processable functional materials, especially organic semiconductors and highly conducting metal inks, and the broad availability of graphical arts printing technologies are at the base of a revolution which will lead to the fabrication of organic opto-electronics devices by means of high-throughput, inexpensive mass production processes. Additive printing techniques offer in fact advantages in terms of process simplification, layer-to-layer alignment, compatibility with large areas, and potential cost reduction compared to subtractive lithographic patterning. In particular inkjet, which is a non-contact technique, offers high flexibility and is compatible with a large range of functional materials. It is particularly advantageous when controlled volumes of inks have to be placed in precise positions on a substrate, as for example in the case of organic photodetectors (OPDs). The possibility to tune OPDs responsivity, therefore enabling a selective photodetection, and to deposit them in principle on substrates of any kind and shape, make them very appealing for various advanced applications.
Project IPPIA aims to demonstrate inkjet printed OPDs sensitive to the visible spectrum of light, suitable for imaging applications. The final objective of this project is to fabricate small arrays of an organic active pixel by integrating OPDs with suitable organic field-effect transistors, acting as an electrical switch, thus paving the way for cost-effective, light-weight, conformable digital imagers.
- Project coordinator: Dr. Mario Caironi
- Duration: 01/09/2011-31/08/2014
Inkjet printing of integrated organic optolectronic devices: from molecular design to a digital X-ray imager
Grant n. 2011–0368, Fondazione Cariplo
We aim at studying the physical, chemical and technological aspects involved in the development of a specific optoelectronic device based on organic semiconductors made of a vertically multi-layered photodiode, serving as conversion element from the photon flux to electrical current, coupled to a Field Effect Transistor as addressing element. This complex optoelectronic device defines a high functionality pixel that, replicated in an array, is the basis of an image detector. The perspective application will be the digital X-ray image sensor array, in which the matrix of pixels mentioned above is coupled to a scintillator for the conversion of X-ray radiation into visible photons, with the aim of replacing the slow, conventional film-based X-ray process with an instantly digitized X-ray image. We choose this application since it is inherently a large-area one, as images to be acquired are often larger than 10x10 cm2 and no convenient focusing solutions are available for X-ray.
- Project coordinator: Prof. Marco Sampietro – “Politecnico di Milano”
- Project partners: CNST@PoliMi-Istituto Italiano di Tecnologia (Mario Caironi), DEIB-Politecnico di Milano (Marco Sampietro), CMIC-Politecnico di Milano (Chiara Bertarelli)
- Duration: April 2012-October 2014
Joint-Lab between IIT and OMET s.r.l. / commercial project
“Roll-to-Roll” printing of polymeric, large area, photovoltaic modules
SOLAR-PRINT will develop a technology to produce, on an industrial scale, large-area solar cells which are lightweight, cheap and easy to integrate, thanks to a continuous “Roll-to-Roll” printing technique. Photovoltaic modules produced by means of this technology will have a competitive cost and they will be “green” thanks to a lower energy consumption needed for their fabrication, to a shorter payback time and to a lower production of equivalent green-house gases. This technology will allow the fabrication of flexible solar cells on a plastic substrate, in the shape of long ribbons, colored and semi-transparent, paving the way to novel applications, and markets, which are innovative, and at the same time alternative with respect to silicon ones.
SOLAR-PRINT is today a joint-lab between OMET s.r.l. (Lecco, Italy) and IIT at the “Center for Nano Science and Technology @PoliMi”. The project benefits from the specific know-how of the CNST and of the “Politecnico di Milano” in the field of organic solar cells (OSCs) and from the printers technology of OMET, company leader in the design and production of industrial printing lines for self-adhesive labels, flexible packaging and paper.
SOLAR-PRINT won the first prize for the “CleanTech AgroFood” section at the StartCup Milano-Lombardia 2011 and was finalist for the “Green” section at the national stage of “Working Capital 2011” promoted by Telecom and PNI.
For further information please visit : http://www.solarprint.eu
- Project Coordinator: Dr. Mario Caironi
- Project Partners: CNST@PoliMi-Istituto Italiano di Tecnologia, OMET s.r.l.
- Duration: July 2012 – July 2014