Printed Electronics

Organic and printed electronics offers tremendous opportunities in creating new and exciting products. Imagine the possibility to produce advanced functionalities on flexible substrates in reel-to-reel processes.

To the right you see an animation illustrating the vision of integrating various kinds of printed electronic devices; push button, speaker, battery and display - all integrated in one system, printed on a flexible material.

Printed Electronics at Acreo is primarily focusing on three application areas: Packaging, Internet of Things and Health Care. We have established a Platform of Printed Electronics components consisting of displays, transistors, diodes, energy sources, interconnects etc. that can be integrated into functional products. The Platform is developed with the target of being easy to integrate and high volume manufacturable.

At Acreo, the development of organic electronics was initiated in the late 1998 by the initiative to the so-called PAELLA project (Paper Electronics for Low cost Applications). The vision of the PAELLA project was to adopt printing technology to the manufacturing of electronics based on polymers, envisioning drastic reduction in production cost as well as the enabling of new exciting applications by adding electronic functions to other materials such as paper and plastics. The project successfully resulted in different demonstrators, as for example displays, ID-functions and sensors.

Co-operation with Linköping University

The research and development at Acreo is conducted in close co-operation with the Organic Electronics group at Linköping University. The collaborative work has successively increased the toolbox of printed/organic electronic devices and circuits as well as introduced new and exciting application areas towards bio-electronics where the bridge between silicon and bio-materials can be crossed by utilising electronic devices relying on electrochemical switching, read more on Bio-electronics. In parallel with the development of the technology platform, a new printing facility has been established where further development of manufacturing processes, in particular reel-to-reel based, of electronic components and systems will be conducted, read more on PEA Manufacturing.

Conducting polymers

Organic polymers are commonly used because of their mechanical properties and low cost processability. In general, plastics have insulating properties and are for example used in plastic coatings on electrical wires to prevent short-circuits. There is, however, a class of polymers, the so-called conjugated polymers, with unique properties such that they will conduct electricity upon “doping”. This class of polymers is also referred to as “conducting polymers”.

This class of material gained a lot of attention after the first report of metallic conductivities in "doped" polyacetylene in 1977 by Alan Heeger, Alan MacDiarmid and Hideki Shirakawa, which rendered them the Nobel Prize in chemistry in 2000. This discovery opened up for the future possibility to construct electronics from plastic materials, since now organic polymers could be used as insulators and semi-conductors as well as conductors, the three necessary building blocks for electronic functions. A large number of conducting polymers have been developed and characterized where optical and electrical properties have been tailored, for example, a specific wavelength is emitted upon the construction of an Organic Light Emitting Diode (OLED). Today, highly stable materials are available and a number of commercial applications can be found on the market such as screens for mobile phones and televisions based on OLED (Organic Light Emitting Diode) technology.

Low-cost manufacturing and flexible substrates

The principal interest in the use of polymers lies in the scope for low-cost manufacturing, using solution processing of film-forming polymers. Thus many researchers have focused on these materials and various manufacturing processes based on printing techniques for what has been referred to as “Organic Electronics” or “Plastic Electronics”. Besides the organic materials, other materials such as silver, gold and silicon are also available as printing inks and thus the terminology has in some instances moved towards “Printed Electronics” in order to include the manifold of available printable functional materials.

The access to a manifold of formulations of functional inks makes it easy to realise the potential for high volume manufacturing on large and flexible substrates by adopting printing technologies known for the high speed (hundreds of m/min) and low cost. This will enable electronics and other functionalities on surfaces and objects where conventional electronics is not commercially viable, and act as a complement to the traditional electronics rather than being a competing technology. By nature the printed electronics area is multi-disciplinary, involving interaction between physics, chemistry and engineering sciences as well as involvement of printing and electronics industry. In order for the printed electronics to reach the market in large volumes further developments on materials, processes and control is needed to ensure high throughput in conjunction with acceptable yield. Going from ordinary static inks to functional inks adds completely new demands on in-line control of the printed objects.

Acreo is a member of the Organic Electronics Association (OE-A); an organization representing the whole value chain in organic and printed electronics. The movie Printed Electronics - Ready to Go, in which Acreo is participating, was released by OE-A on February 18th 2011.