It is inevitable that the choice of best markets for printed electronics will change as developers establish the strengths and weaknesses of their products and learn which users are keen and which are not.
Five years ago, most of the developers of printed transistor circuits TFTCs were prioritizing RFID as the first commercialization of their products. Then it was realized that the specification creep in key RFID standards was taking the parameters further and further away from the inevitably primitive, initial capability of TFTCs. That may be a Pyrrhic victory for the silicon chip people because even they can not address such complexity without eye watering trading losses, but it still does the printed electronics industry no good at all. In addition, it was realized that one failed transistor kills an RFID tag whereas, in a backplane driver for displays, you only lose a pixel. Indeed, the rapid progress with several flexible display technologies made it clear that there would be a huge future in backplane drivers for them and the specifications are realistic and achievable with printing technology. And so it was displays became the favoured priority for commercialization of TFTCs although IDTechEx also saw enormous potential in toys and merchandising.
Anti-counterfeiting, fraud prevention, smart packaging
Thin Film Electronics AB of Sweden, printing thin film, non-volatile memory on low cost flexible substrates, sees its opportunities somewhat differently. Three years ago it talked of smart labels, smart packaging, smart cards, RFID and “low cost electronics such as toys”. Now it plans to evolve the technology from simple, slow, transistor driven, memory to RF interfaces on memory and then memory with co-deposited displays as well. Matching all that to the marketplace now has them talking firstly of anti-counterfeiting and fraud prevention (also an early priority for Poly IC of Germany with printed transistors) and toys and games. Then will come logistics/ID. Then comes smart packaging, displays with memory and finally RFID.
We wish TFE and Poly IC well with anticounterfeiting and fraud prevention. However, we note that Holotag, Link-Sure, Flying Null, Remoso, Lintec, Miyake, Navitas, Remoso and CWOSRFID, when they realized that their chipless tags had too little data for mainstream RFID, thought that their escape route was a few bits in a label for anti-counterfeiting and fraud prevention and most of them have either gone bankrupt or abandoned the chase. HID succeeded with a 25 bit (deliberately eccentric) Barkhausen effect array of microwires in two dollar secure access cards, selling about 60 million, and later Menippos sold gaming cards discussed later in this article but that was all. TFE needs adequate printed RFID logic and air interface and Poly IC needs adequate rewriteable memory capacity.
Happiness is a standard ticket
Those developing printed transistors will find life much easier when they can meet such things as the standard ISO 14443 transport ticket specification with 256 bits of read write memory and an HF (13.56MHz) air interface. This does not call for securely segmented memory let alone microprocessors. The Chinese railway system will need three billion yearly and even Moscow will take up to 360 million yearly. Currently the price is about 20 cents for an unprogrammed ticket and 50 cents when programmed and overprinted, though the highest volume orders will be a little below this. On a ticket, space is not too much of a constraint for printed transistors with their currently large feature size. However, that amount of printed memory with adequate yields has yet to be announced. They will get there. IDTechEx sees $40 million being spent on such tickets in 2011 and that forecast will be sharply increased if the planned big orders in China and certain other countries come to pass.
Interest in simpler tickets and badges as a beginning
Two years ago printed RFID badges by ACREO of Sweden were used in the IDTechEx Printed Electronics USA conference. This was the ink stripe type of RFID not incorporating transistors but having PEDOT printed organic stripes, each one representing one bit of data and read by capacitive coupling. It has still not been fully commercialized but a similar PEDOT ink stripe RFID was commercialized in 2006 by Menippos working with printed systems GmbH in Germany. It was in the form of game cards.
Now printed organic RFID tickets based on transistors, and therefore potentially more versatile, are set to be used in a field trial at the Organic Electronics Conference. Unlike ink stripes, they will work at the standard RFID frequency of HF (13.56MHz). This is the most popular RFID frequency used today.
The circuits are the first printed low-cost organic tickets, according to Cintelliq Ltd. of the UK, the organizer of the conference, and have been developed under the auspices of PRISMA, a collaborative research project on printed smart labels with European Union funding. The tickets will be manufactured by printing company Bartsch GmbH in Germany and with PolyIC printed TFTCs.
During this first trial, the printed tickets will be used to collect statistical data. Four reader stations developed by PolyIC and about 1,000 TFTC tickets converted by Bartsch will be used to monitor the flow of attendees during the two-day conference and exhibition. The trial will herald the development of a wider range of printed RFID applications, in public transportation and logistics.
For more on commercialisation of printed electronics attend one of the annual IDTechEx conferences with exhibition and optional masterclasses. They include Printed Electronics Asia, Printed Electronics USA and , in 2008, the next Printed Electronics Europe.
By Dr Peter Harrop