fantastic plastic

Cambridge Display Technology (CDT) and Toppan Printing

have produced a number of 5.5 inch full color active matrix polymer OLED (P-OLED) displays using a roll printing method. A demonstrator will be shown at the SID conference in San Francisco. The displays - believed to be the first of their type ever produced - are the result of close co-operation between the two companies and part of their joint development activity announced in February 2005.

Solution processing of P-OLED displays is more commonly associated with inkjet printing, and the companies believe that roll printing represents a promising alternative production technique which offers the potential for very good display uniformity, very high display resolution and low capital and operating costs. […]

The technique is based on relief printing, a well-established method for the transfer of soluble materials onto a range of substrates, but which has been developed by Toppan into a highly precise technology capable of producing patterned pixels of small size and highly uniform distribution. The companies believe that the process is capable of scaling to large substrate size and very high resolution, potentially over 200 ppi.

press release

NanoMarkets predictions for the OLED and e-paper, smart packaging, and thin-film photovoltaics industries:

Markets for OLED and Paper-Like Displays to Total $10.2 Billion by 2011:

• combined sales of OLED displays and paper-like displays will reach $10.2 billion by 2011 and then go on to reach $14.7 billion by 2013.
• shelf-edge displays will be the biggest opportunity for the paper-like display business in the next few years, generating $1.2 billion in annual revenues by 2011.
• OLED televisions will reach $2.2 billion in revenues in 2011
• by 2011, flexible displays will account for $1.7 billion in revenues.

Smart Packaging Market to Reach $4.8 billion by 2011:

• The global smart packaging market will grow to $4.8 billion in 2011 and reach $14.1 billion in 2013
• Smart packaging will account for over $1.1 billion in printable electronics components by 2011 growing to $4.2 billion in 2013
• Smart packaging will also consume $1.1 billion in printable and chip-based RFID tags by 2011

Thin Film and Organic Photovoltaic Market To Reach $2.3 Billion ($US) in 2011:

• Integrated building and construction products such as PV enabled roofing and window materials are projected to be the largest market opportunity measuring $800 million ($US) in 2011 with large project and consumer electronic products the second and third largest market opportunities.
• On the materials front, amorphous silicon, the best established of the various thin-film PV materials, will represent an $800 million ($US) opportunity followed by organic and hybrid organic/inorganic materials and then CIS/CIGS.
• Thin film/organic PV is also generating buzz in the industry and several companies have received large VC rounds. Major multinationals are also supporting this technology as Honda has announced it will soon start full-scale production of thin film PV and Shell has just sold off its conventional PV business to focus on thin film. On the other hand, NanoMarkets points out that thin film and organic PV is also a technology space that has received its fair share of hype and controversy with competing claims by different manufacturers on where and how it can be applied and disputes over conversion efficiencies and costs per watt.

According to Displaybank

Japans’ Tohoku Pioneer has launched mass production at its new plant dedicating to producing white organic light-emitting diodes (OLEDs) for mobile handset backlights (BLUs), the Nihon Keizai Shimbun reports. The company is first to start mass production of white OLEDs in Japan. With this launch, the OLED plans to ship white OLEDs from the plant in Aomori Prefecture to overseas mobile phone vendors this month.

The Georgia Tech Center for Organic Photonics and Electronics (COPE) and Solvay announced a $3 million deal for OLED research today.

COPE has already developed a unique material platform for OLEDs that may be deposited over large areas by ink-jet printing and patterned using standard photolithography. Tech researchers have found that exposing the material to ultraviolet light leads to hardened materials that are insoluble and maintain stability under high temperatures. This allows researchers to build a multi-layered solid-state device from liquid materials. […]

COPE, through the research group of Jean-Luc Bredas, already conducts research activities with the University of Mons-Hainaut in Belgium. Georgia Tech has two international campuses, Georgia Tech Lorraine in Metz, France, and Georgia Tech Singapore. […]

In addition to Marder and Bredas, two other principals at COPE are Bernard Kippelen, associate director of COPE and professor in Tech’s School of Electrical and Computer Engineering and Marcus Weck, associate professor in the School of Chemistry and Biochemistry.

DuPont has announced solution-processable small molecule OLED materials, enabling low-cost deposition techniques previously only possible with polymeric OLED materials.

DuPont’s latest technological achievement enables — for the first time — the combination of high performance and long lifetime of small molecule OLED materials with a printing process that is substantially lower cost and more scalable to larger display sizes than the industry incumbent processes, such as vapor deposition. Through a combination of innovative processing device architecture and new materials, DuPont has demonstrated printing of small molecule OLED materials from solution.

DuPont has achieved lifetimes of the three primary colors each exceeding 10,000 hours of white lifetime (or 40,000 hours for a typical video) at the brightnesses required for a 200 nit display. With this development, DuPont has demonstrated that OLEDs can be manufactured at high yields and low total cost.

The Princeton Institute for the Science and Technology of Materials (PRISM) has been awarded a $1.7M R&D contract by the U.S. Display Consortium (USDC)

to develop the process technology and know-how to produce amorphous silicon thin film transistors (a-Si TFTs) on a clear, high temperature-capable polymer foil substrate.

[…] organic substrates cannot withstand typical TFT semiconductor on glass processing temperatures of >300°C. The Princeton program is based on a new type of clear, flexible polymer substrate that is capable of use at these “glass-like” processing temperatures.

The two-year program has several important milestones. For example, by the end of Year 1, a best effort will be made to demonstrate an electrophoretic test array and an OLED test array on the plastic substrate. […]
The principal investigators, Wagner and PRISM director Dr. James Sturm, have been working on experimental substrates for some time and have made a-Si TFTs at 280° C with performance nearly identical to typical TFTs made on glass. Applied Materials’ subsidiary, AKT, will collaborate to investigate the scale up of these materials using industry-standard fabrication tools.

A research team including Stephen Forrest and Mark Thompson have published their work on
“Management of singlet and triplet excitons for efficient white organic light-emitting devices”
in Nature (440, 908-912; 13 Apr 2006)

From the Scientific American:

“A 100-watt bulb is about 15 lumens per watt and we’re at about 25 lumens per watt just on the lab bench,” Forrest says.
The diode also requires a lower voltage than purely phosphorescent devices do thanks to its fluorescent component […]
Challenges remain before light-emitting ceilings can become common. Among other things, scientists will need to find a material to encase the sensitive diodes. “This doesn’t need a vacuum but it does need a moisture barrier and that can be expensive,” Forrest explains. “The biggest barrier to large scale production is simply cost. It costs very little to make a light bulb today.”

In the abstract of the of the artice the increased energy efficiency of white OLEDs compared to incandescent lighting and the compatibility with low-cost manufacturing methods are mentioned, as well as a few details of the new approach:

The most impressive characteristics of such devices reported to date have been achieved in all-phosphor-doped devices, which have the potential for 100 per cent internal quantum efficiency: the phosphorescent molecules harness the triplet excitons that constitute three-quarters of the bound electron-hole pairs that form during charge injection, and which (unlike the remaining singlet excitons) would otherwise recombine non-radiatively.
Here we introduce a different device concept that exploits a blue fluorescent molecule in exchange for a phosphorescent dopant, in combination with green and red phosphor dopants, to yield high power efficiency and stable colour balance, while maintaining the potential for unity internal quantum efficiency.
Two distinct modes of energy transfer within this device serve to channel nearly all of the triplet energy to the phosphorescent dopants, retaining the singlet energy exclusively on the blue fluorescent dopant. Additionally, eliminating the exchange energy loss to the blue fluorophore allows for roughly 20 per cent increased power efficiency compared to a fully phosphorescent device.
Our device challenges incandescent sources by exhibiting total external quantum and power efficiencies that peak at 18.7 +/- 0.5 per cent and 37.6 +/- 0.6 lm W(-1), respectively, decreasing to 18.4 +/- 0.5 per cent and 23.8 +/- 0.5 lm W(-1) at a high luminance of 500 cd m(-2).

Previous white OLEDs (WOLEDs) suffered from poor colour stability due to the limited lifetime of the blue electrophosphorescent component. A note on the increased lifetime compared of these new WOLEDs, from the BBC:

Previous attempts to make OLEDs like this have largely failed to make an impact because traditional phosphorescent blue dyes are very short lived.
The new polymer uses a fluorescent blue material instead which lasts much longer and uses less energy.

EETimes is reporting on a new printhead using an OLED light source.

Epson Corp. said it has developed a print head using an organic light-emitting diode (OLED) light source, which is touted as achieving printing performance comparable to that of laser printer heads.
Sumitomo Chemical Co. Ltd. collaborated with Epson on the prototype printer head from the material side, supplying red polymer OLED material. […]
Epson intends to merge its low-temperature polysilicon TFT technology with the OLED technology to build a one-body printer head module with OLED and IC integrated on it.

Printers using an array of inorganic LEDs instead of a laser as light source have been around for a while. From an article from 2002:

LED (light-emitting diode) page printing - invented by Casio, championed by Oki and also used by Lexmark - was touted as the next big thing in laser printing in the mid-1990s.

Unlike laser printers, LED printers do not require any moving parts (mirrors) to selectively illuminate the photo-receptive drum, but are limited in resolution by the size of the LEDs.

According to a report by Displaybank

Overall OLED shipments reached more than 61 million units for the year 2005, and revenues hit almost US$600 million, according to Displaybank (CEO Kwon Sang-Sei), a market research firm.

The clear leaders in 2005 were Taiwan (27 million units) and Korea (22 million units), followed by Japan (8 million units).

BusinessWeek has a story on electronic ink applications, such as Hitachi’s electronic paper advertisement displays, updated via wireless connection.
They remind us of the fact that modern information technoloy has not led to the once envisioned paper-free office.

But the fact is, paper hasn’t gone away. The spread of the Internet and the rise of the PC have made information ever more accessible, leading not to the death of paper but to its proliferation. In 2004, worldwide paper production was roughly 400 million tons, compared with about 300 million in 1995, according to Japan Pulp & Paper statistics.

It remains to be seen whether or how soon e-paper will replace real paper. Applications such as rewritable shop price tags and billboards, where e-paper can provide added functionality, compared with traditional paper,

could help the market for e-paper surge to nearly $900 million by 2011, from $2 million last year, according to Tokyo-based market watcher Techno System Research.

The article goes on to mention colour electronic paper and printable OLEDs.
It’s cleary a business article, so we can forgive them for confusing some of the technical details:

Despite their differences, LCDs and OLEDs share two important traits: They can quickly change what they display and don’t need a backlight, so the only time they use power is when text or images change.

Of course LCDs and OLEDs are fast compared to most e-paper types, but, unlike bistable e-paper, constantly require power. Also, most LCDs do need a backlight (or frontlight), at least for low-light situations.

LG.Philips LCD, one of the world’s leading TFT-LCD manufacturers, announced today that it has entered an evaluation agreement for active matrix organic light emitting diode (AMOLED) development with Eastman Kodak Company. Under the terms of the agreement, LG.Philips LCD and Kodak will jointly evaluate display technologies for mobile displays and consider other opportunities, including the development and supply of AMOLED technology and products.
Budiman Sastra, executive vice president and CTO of LG.Philips LCD, said, “This agreement brings together our leadership in TFT technology with Kodak’s expertise in producing OLED materials and processing technology. Our goal is to work together seamlessly to develop future business opportunities in the AMOLED industry.”

NE Asia Online on the 2006 OLED Technology Report by DisplaySearch

Revenues of OLED industry is expected to total over US$500M in 2005, up 18% Y/Y, according to the 2006 OLED Technology Report from DisplaySearch. OLED display makers are in transition from passive matrix to active matrix centricity, not unlike LCDs in the early to mid 1990s. The difference is that AMOLED display makers are expected to ride the benefits of the existing TFT infrastructure created for LCDs.

Table 1 OLED Display Revenue by Application (US$ million)

Table 2 Organic Material Forecast (US$) vs Display Production

Universal Display Corporation announces a prototype full-colour flexible active-matrix OLED display at the USDC’s 5th Annual Flexible Displays & Microelectronics Conference in Phoenix, Arizona.

In the paper titled “Full Color 100 dpi AMOLED Displays on Flexible Stainless Steel Substrates,” Dr. Anna Chwang will highlight the performance characteristics of a novel flexible, full-color AMOLED display prototype that is based on the Company’s proprietary phosphorescent OLED (PHOLED™), top-emitting OLED (TOLED®) and flexible OLED (FOLED®) technologies. The full-color AMOLED prototype also uses poly-Silicon thin film transistor (TFT) backplanes designed and fabricated by PARC, a subsidiary of Xerox Corporation, and was encapsulated by Vitex Systems.

The four-inch diagonal display can portray a variety of images, including full-motion video. This advance is significant in proving the fundamental feasibility of the Company’s approach and also clearly demonstrates several key performance advantages. The display (without external drive electronics and package) is approximately 0.1 mm thick and weighs a mere 6 grams. The comparable glass-based LCD would be approximately 1.0-1.5 mm thick and weigh 20-30 grams.

GE Global Research is presenting details on its successful development of a substrate system for flexible organic light-emitting diodes (OLEDs) at the Flexible Displays & Microelectronics Conference, Feb. 6-9 in Phoenix, Ariz. The system features a developmental high-temperature Lexan(1) polycarbonate (PC) film from GE - Plastics combined with a transparent, ultra-high-barrier coating to help protect the OLED device against oxygen and moisture. This research, jointly funded by the U.S. Display Consortium (USDC) and GE, is designed to address the critical need for plastic substrates that can enable cost-effective, lightweight, flexible organic displays. Min Yan, GE materials scientist, will give a presentation on the new substrate system, which is currently being produced in batch mode and will ultimately be moved to a roll-to-roll process for cost efficiency. In addition, GE - Plastics is featuring a variety of plastic films for electrical/electronic display applications during the exhibition. […]
The GE system utilizes the high temperature resistance and high clarity of transparent Lexan film - properties that enable the 125-micron-thick substrate to withstand the heat involved in OLED fabrication and to allow optimal light transmission from the device. The unique graded organic/inorganic barrier coating, which is applied using plasma enhanced chemical vapor deposition, meets the stringent requirements for fabricating OLEDs. The transparent coating prevents degradation of the device from oxygen, moisture, chemicals, and electrical conductivity while promoting light transmission.

(1) Lexan and LNP are trademarks of General Electric Company.

Last year (July 2005) revealed a keyboard design with customisable keys using individual OLED displays. It looks like we will have to wait (at least) until the end of 2006 for this, but they are now taking pre-orders for the mini three keyboard. Same design, but only three keys.