Printable electronics - electronic components manufactured with printing technology, like that used for printing newspapers, magazines, posters or other printed material - is finally nearing commercial availability.
Printed Systems GmbH of Germany, for example, used roll-to-roll manufacturing and printing technology to continuously produce the identification (ID) cards used in an online soccer game, in August 2006. The onboard memory stores 16-bit data, making possible a total of 65,536 codes, with each code allocated to a specific team player.
In 2007 PolyIC GmbH & Co KG of Germany is planning to ship radio frequency ID (RFID) tags using the 13.56MHz waveband, initially to provide a means of verifying product authenticity.
Volume production applications such as organic electroluminescent (EL) panels and dye-sensitized solar cells are also ramping up. The organic EL panels manufactured by Dai Nippon Printing Co Ltd of Japan, for example, using printing technology now in development, have already sample-shipped to selected users in the form of area color sheets for posters and similar applications. Evaluation of dye-sensitized solar cell samples is continuing as well. Multiple equipment manufacturers are now evaluating the operation of dye-sensitized solar cells from Peccell Technologies Inc of Japan, for example.
Brilliant Individuality
Printable electronics has attracted considerable attention for many years for a range of new potential component technologies. It can offer mechanical flexibility, and manufacturing cost and weight reductions of 90% or more. Compared to products based on Si technologies, such as integrated circuits (IC) and displays, only relatively simple circuit configurations have been possible and electrical characteristics have been poor, among other problems. Device life has generally been only several thousand hours, and no more than two years even for "long-life" items. As a result, most people in the industry had thought it would still take several years for the market to really get going.
That has all changed, though. Even with inferior performance, technology has already reached the commercial level for specific applications. The memory device built into the ID card by Printed Systems is actually a capacitor made from conductive and insulating films and a polymer material, and uses no thin-film transistors (TFT). The RFID tag to be marketed by PolyIC has only several hundred organic TFTs, and an 8-bit read-only memory (ROM) for data. Neither application can handle more than a very small amount of data, but that's sufficient for limited-application ID cards. The sample Dai Nippon Printing organic EL panels under evaluation do not display a matrix representation of an image. While the luminance life is short, "Performance is adequate for poster applications. The only question is whether we can justify the price," explained Motohiro Oka, deputy general manager of the Research & Development Center there. The conversion efficiency of dye-sensitized solar cells is only 5% to 6%, but according to Prof Dr Tsutomu Miyasaka, professor at Toin University of Yokahama of Japan, visiting professor at Tokyo University of Japan and president and chief executive officer (CEO) of Peccell Technologies, "We have customers ready to use them in commercial products if we can assure a three-year service life."
In many cases, the components available through printable electronics offer a range of highly individual characteristics. The ID cards made with printable capacitors are much more difficult to duplicate than barcodes. Compared to IC chips, products like ID cards and RFID tags can be produced easily - and cheaply. There isn't even a market for posters with display functions, such as implemented by the organic EL panels used for area color displays. Until now, there have been no solar cells that could be pasted on walls, carried around like notebooks, or that would keep on working if dropped. As Dr Toshihide Kamata, group leader, Research Institute of Photonics, Organic Semiconductor Device Group, National Institute of Advanced Industrial Science & Technology (AIST) of Japan explained, "I think there are a lot of product ideas out there that never happened simply because people never noticed the possibilities."
From Niche Markets...
Commercial printable electronics became possible for several reasons, notably improved performance, improved manufacturing stability, and, although admittedly still short, service lifetimes of several thousand hours. These characteristics can also be expected to show improvement through modifications in operating frequency, integration level, device life and other points, making it possible for them to be used in a wide range of application sectors (Fig 1).
The manufacturing of commercial printable electronics is also being helped along by the continuing penetration of printing technology into electronic component manufacturing processes. There are more and more examples, including forming color filters and alignment layers on liquid crystal display (LCD) panels, or microlenses for backlights (Fig 2). The development of inkjet printing technology to form the metallization on printed wiring boards (PWB) is also continuing.
(Continue to the next page)
Nikkei Electronics |
Nikkei Monozukuri |
Nikkei Automotive Technology |
|---|---|---|
 |
 |
 |
| The magazine for electronics designers and managers. | Design You Won't Regret - How to Reduce the Risk of Accidents | The comprehensive automotive technology magazine. |
Copyright © 1995-2010 Nikkei Business Publications, Inc. All rights reserved.
All editorial content and graphics on this Web site may not be reproduced in whole or in part without the express permission of the copyright owner.
