Some impressions from Printed Electronics Europe
Apr 11, 2011 Dr Peter Harrop
Printed Electronics Europe in Düsseldorf grew again, remaining Europe's largest event on the subject. Here are a few impressions of technical and marketing trends in subject picked up at the intensive conference sessions and busy exhibition.
Consumer packaged goods CPG companies see the relevance and were there in considerable numbers, with many packaging, printing and printed electronics suppliers now targeting this sector. Although the CPG companies do not develop their own PE technology an increasing number of other giant corporations that are actual or potential end users do develop the technology.That goes from oil to atomic energy.
Indeed, this year De la Rue, the banknote leader, revealed that they are also now a potential volume end user that has been secretly developing their own PE capability for some time. This consists of printing electronics on paper that can capture power from a mobile phone. This was part of an increasing interest in paper electronics generally in the industry. For example, Prof Huebler of the Technical University of Chemnitz described wide area unprotected paper organic photovoltaics for Third World countries though many challenges remain for this.
The scope for making a huge variety of useful circuits without using the elusive printed transistors continues to surprise. For example, this year saw free working samples, for all delegates, of new diode-based crushed silicon thermistors on paper and the electronic "Best in Exhibition" voting form both with no transistors. Indeed the world's first fully printed electronically enhanced magazine, demonstrated at the show, and had no transistors.
The only meaningful orders taken for printed transistors remain those taken by Kovio for its nanosilicon versions, including mass transit day tickets. Commercially successful printed organic transistor circuits were conspicuous by their absence. Some agreed with Samsung that the window of opportunity for printed organic transistors is closing fast as the limitations of printed zinc oxide transistors are overcome, such as high annealing temperature, poor printability and lack of p type.
Professor Elvira Fortunato showed how her team at the New University of Lisbon has even progressed to CMOS using CuO and SnO for the previously elusive p type and GaInSnZnO for n type, reducing the amount of expensive indium previously employed. Indeed, the University of Cambridge in the UK has got quite good ZnO transistors printed with no indium. In answer to questions she seemed to be saying that ZnO transistors are now ready for prime time given their superior electrical properties.
Organic photovoltaics is showing poor progress with its primary limitation which is life of only a few years but the good news is that an increasing number of potential users can still use it and indeed they sometimes favour it over technically superior inorganic alternatives partly because of environmental and health credentials. For example, it is felt that a baby can safely bite it though full investigation of this is not yet reported.
Overall, though, it seems likely that the flexible PV market will grow huge and fragment into large niches, with the result that there will probably be a prosperous future for most of the very different chemistries reported at the event.
A considerable number of sensors of movement, heat, proximity and more were demonstrated, including in wide area form. In fact, the ability of printed electronics to do wide area products impossible with conventional electronics was generally much in evidence. Another recurrent message was that up to 53% cost saving is coming from replacing conventional thin film deposition with printing. However, nominally the simplest part of circuits, the conductor, is proving to be difficult to improve when it is so often needed to be transparent. No one is landing large orders for replacement of RF sputtered indium, the industry favourite, despite indium price concerns and the cracking when ITO is bent around less than a 2.5 centimeter diameter.This is holding up a host of new product ideas such as the big screen intended for rolling into the mobile phone.
Heraeus-Clevios was host of a fascinating plant visit from the event. It now offers finely patterned PEDOT-PSS as a flexible transparent electrode solution, combining two previous candidate technologies. Maybe this is a way through.
The event revealed that there remains a huge interest in the intractable problems of flexible OLEDs. This is because a strident market need remains unfulfilled. In this case there is no prospect of an inorganic alternative saving the day if affordable, long life OLEDs never appear.
Dr Peter Harrop, Chairman of IDTechEx gave the last presentation of the event - he showed how a new front has opened up with electric vehicles needing PE. Circuit maker T-Ink and printed, flexible battery maker Planar Energy have even refocused from CPG, consumer electronics, novelties and similar applications to prioritise electric vehicles as the prime target for their PE skills.
For T-Ink that means getting up to 40% of cost, weight and volume out of vehicle control clusters and wiring by printing. Printed electronics GmbH also has something in this space. For Planar Energy it means printing reel to reel the forthcoming third generation fully solid state inorganic lithium-ion batteries to replace second generation versions many of which are organic and involve a gel as well as solid electrolyte. There was therefore great interest in the forthcoming IDTechEx "Electric Vehicles- Land, Sea, Air" event taking place in Stuttgart in June. PE start up Flexible Electronics Concepts and flexible solar users Asola, Kopf Solarschiff, Teledyne and Grove Boats SA will be among those exhibiting or speaking.
By contrast, although a few healthcare companies were present, the PE message has not really got through to this industry. The greying of the population in most countries - particularly severe in Russia, Italy and Japan soon - is going to hit them with huge opportunities when they change course. The vital need for low cost disposable testers, monitors and drug delivery systems - none of which are possible without PE - is largely deferred for another day.
For more attend: Printed Electronics USA 2011.