"We build intelligence into everyday objects"

Illustration | Bosch Rexroth AG; pr+co GmbH
Marginal Column
Photo | Prof. Baumann

Prof. Dr. rer. nat. Reinhard R. Baumann, has since 2006 occupied the chair for Digital Printing and Imagery Technology, in the Printing and Media Institute at the Technical University of Chemnitz, Germany.

He has been responsible for the department called “Printed Functionalities” at the Fraunhofer Institute for Electronic Nanosystems (ENAS) in Chemnitz since 2007.

His research focuses on future applications of graphic technologies for digital production of smart objects, including printed flexible electronics.

Photo: Prof. Baumann

Printed electronics can already be found in many applications. But what does the future hold in store for these so-called “printed functionalities”?

 

Professor Reinhard Baumann of the Technical University at Chemnitz, Germany, tells us about the advantages, possible applications, and environmental compatibility of this new technology.

What do you think are the greatest benefits that printed functionalities can offer?

The attraction for me is that with printed functionalities we need to use expensive materials only in places where they are actually needed. This is exactly what happens during the printing process. Once an image has been applied to an object, it is not etched away, which is the case with lithography. I believe that printed functionalities give rise to electronics that do not necessarily have to compete with traditional silicon electronics. Everything depends on the application, even though the technology involves much lower investments for production equipment and uses materials sparingly. Silicon electronics will always have an advantage in high-performance applications such as really fast processors. Printed electronics, however, are ahead by lengths when dealing with high volumes and larger surface areas.

What applications do you foresee in the next ten to twenty years?

We foresee for this period significant progress in the development of suitable materials. At the moment, this is still a critical factor, since there are only a few semiconductors that can be produced for industrial applications. With the advent of better materials, we will be able to improve charge carrier mobility and reduce sensitivity to oxygen and water. This progress in materials, coupled with improved resolution and registration constancy in the printing process, will result in faster circuits. Improved profitability for the new printed products will result in far wider use in the packaging industry as the need for expensive barrier layers will be eliminated.

Which areas are most likely to be affected by the printing of functional materials in the future?

Generally speaking, functional printing already contributes to integrating intelligence into many everyday items. This supports mass use of these “printed smart objects”. One of their most essential properties is their ability to communicate – wirelessly – with each other and with computer systems and networks. Today, RFID tags are primarily produced with all-purpose antennae. However, these antennae are not in all cases perfect for products and their dielectric parameters. Let’s look at a milk carton that is fitted with an all-purpose antenna. The water in the milk attenuates the antenna’s transmission power, which means that a standard tag will not achieve the required communication quality. Only when RFID antennae have been optimized for this particular purpose and can be printed along with the brightly colored images on the packaging will it be possible to achieve optimal communication quality and lower cost levels. Thanks to the lower costs, antennae can then be adapted to suit every new type of packaging. When this happens, the new business model will play a major role in expanding and propagating the “internet of things and services”.

The range of applications for this new technology appears to be broad, in sensors and transistors but also in rollable displays. Is all this possible with one and the same process?

Generally speaking, we expect that all these different applications will have to be produced with differing printing technologies. The crux is deciding which technology is the most suitable in each case, taking all the technical and commercial aspects into consideration. Gravure printing would appear to be the most feasible method for producing large surface displays or sensor arrays. In the future, it should be possible to print fine contacts and simple logical circuits with economical inkjet technology.

How would you rate the environmental compatibility of the new process?

Printed electronic circuits lower costs and at the same time reduce resource consumption, simply because less material and less energy are used – this is eco-friendly. With today’s understanding of sustainability, we must engineer products, right from the very outset, to ensure that they contain no hazardous wastes. We are on the safe side with the classes of materials currently on the horizon. Any auxiliary materials that are necessary today and that do not fulfill these criteria will most certainly disappear during the innovation process.