Category Archives: OLEDs

Unidym signs OLED agreement


January 15, 2007

Jan. 15, 2007 — Arrowhead Research Corp. of Pasadena, Calif., announced that its majority-owned subsidiary, Unidym, has entered into a collaborative agreement with the Institute of Materials Research and Engineering (IMRE) in Singapore to develop organic light emitting diodes (OLEDs) incorporating transparent electrodes made of carbon nanotubes.

Under the terms of the agreement, Unidym will provide IMRE researchers with access to its proprietary, carbon nanotube-based, transparent electrodes which IMRE will incorporate into its OLED devices.

According to iSuppli Corp., the market for OLEDs was $408 million in 2004 and is expected to reach $2.9 billion by 2011. Arrowhead says carbon nanotube-based transparent electrodes have the potential to improve the performance of OLEDs while also reducing their production costs.

“We believe IMRE is a world leader in OLED technology and are pleased that Unidym has entered this collaboration with such a distinguished institution,” said R. Bruce Stewart, Arrowhead Research chairman, in a prepared statement. “We will continue to look for strategic partners to integrate Unidym’s transparent electrodes into optoelectronic systems.” Arrowhead has an 88 percent ownership stake in Unidym.

January 3, 2007 – Universal Display Corp., a developer of OLED technologies and materials, and Nippon Steel Chemical Co. Ltd., a provider of super-purified OLED materials, say they have achieved a “significant enhancement” in the performance of green phosphorescent OLEDs, doubling the device’s operational lifetime while maintaining existing color and efficiency characteristics.

The device, encompassing UDC’s green phosphorescent emitter and proprietary blocking layer material with Nippon Steel’s new green host material, achieved 60,000 hours operational lifetime with initial luminance of 1000 candelas/sq. m. It also exhibits high luminous efficiency of 65 candela/ampere and external quantum efficiency of 18% (also at 1000 candelas/sq. m). The lifetime represents more than a two-fold increase in stability compared with previously reported performance, the companies noted.

UDC and Nippon Steel already collaborated for vacuum-deposited phosphorescent red OLEDs, and are now working on blue phosphorescent materials. “We are determined to realize full-color phosphorescent OLED materials, including blue phosphorescent OLED materials, which is the next milestone of the collaboration,” said Yasuhiro Shimoura, executive officer and GM at Nippon Steel’s organic display materials division.

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June 26, 2006 – Austria-based Nanoident Technologies AG is hoping its ultra-thin, organic semiconductor-based nanolayers can help the company slide into market faster than previous nanotechnologies with applications in displays, sensors and biometrics.

The company announced a new division on Monday that is focused on the biometrics field. Nanoident intends to show off its photonics platform — aimed at easing the creation of commercial organic photonic devices — in a new family of biometric sensors, said Nanoident CEO Klaus Schroeter.

Using organic semiconductor alternatives to silicon — specifically, conjugated polymers with proprietary additives — Nanoident prints electronic circuits on surfaces using industrial inkjet printers, a significantly cheaper alternative to the billion-dollar semiconductor fabs typically required for such work, said Craig Cruickshank, a principal analyst at Cintelliq, a consultancy that tracks the sector.

Cruickshank said that by building on previous work, which includes Nanoident’s roots in organic light emitting diodes (OLEDs) and industrial inkjet printing, Nanoident may be able to cut the technology’s time to market

“There’s already a proven use of the materials and process,” he said. “They’re building on the technology that’s already available. It’s not some new material, system or deposition.”

At the same time, Nanoident’s combination of OLED and sensor technologies is novel, according to Cruickshank.

“Nobody else has done it,” he said. “They’ve combined them and come up with a production system for it.” He cited Nanoident’s background in the field and its focus on production as among the qualities that would help it come through on its promise to deliver devices by the end of the year.

“Market adoption is always the biggest challenge, but these are all good areas to use light emissions and touch,” he said, stressing that Nanoident’s organic materials have a large-area advantage over silicon, which is limited by wafer size and expense.

Nanoident prints organic semiconductor layers 20 to 30 nanometers thick. Although the materials may be expensive, there is so little used that the printing technique saves money, according to Schroeter.

He said there is interest in the technology from cell phone companies. They do not have space for traditional biometric sensors but are interested in technology from Nanoident that could read a user’s fingerprint for identification.

Schroeter said products from Nanoident’s new Biometrics GmbH will range from simple yet secure fingerprint sensors to more sophisticated solutions that combine different biometric measurements made possible by Nanoident’s fusion of OLED displays and sensors.

In addition to reading a fingerprint, the device could also defend against attempts to circumvent it by identifying other biometric traits. For example, a sensor could identify a user by the inner dermal tissue structure of their finger, Schroeter said.

The company’s approach allows the creation of an entire biometric system on a smart card, Schroeter said. “The big thing is, we can … get rid of the large biometric databases used by governments and large banks,” he said. “They don’t really want to store biometric user data. The best way to store the biometric data is directly in the smart card.”

Nanoident is also working on life sciences applications, such as medical diagnostics, and in the industrial sector, which will soon be the basis of another Nanoident announcement around its photonics platform, Schroeter said.

Schroeter said the 30-employee company would grow rapidly in the next few years as it competes in a sensing market expected to grow to more than $250 billion by 2025, according to IDTechEx, a market research firm. He said Nanoident would add another 20 employees with the new biometric division. The division will be led by Alain Jutant, whos prior experience in biometrics and image sensors includes positions at ATMEL and Thomson-CSF Semiconductors.

June 14, 2006 – Researchers at Advance Nanotech Inc. and the Center for Advanced Photonics and Electronics (CAPE) at the U. of Cambridge, UK, say they have developed novel composites made from organic polymers and nanostructured materials that provide “printable” semiconductors for low-cost inkjet print manufacturing.

Future electronic and optoelectronic fabrication techniques will require polymer materials that can be inkjet printed while exhibiting suitable carrier mobility and current transport characteristics. Today’s best-available polymer materials have conductivity several orders of magnitude lower than silicon, noted Paul Beecher, a CAPE researcher working on the project. “A one nanometer gap between the molecules of an organic polymer is sufficient to prevent effective charge transport,” he said. “Our technology explores an alternative approach to overcoming the poor electrical properties of most organic semiconductors by exploiting the enhanced conductivity brought about by selected nanomaterials.”

After a year of work, the scientists say they have optimized the chemical treatment of nanostructured materials and effectively disperse them in a range of polymers, and successfully incorporated selected nanomaterials into organic polymers. The result — insulating materials turned into composites — show promising transistor characteristics, and have proven “quite stable,” with no tendency to quickly form aggregates in solution, and thus suitable for inkjet print manufacturing.

Peter Gammel, CTO at Advance Nanotech, pointed to estimates from IDTechEx of a potential $30 billion market for printed electronics by 2015, and surging to $250 billion by 2025. Possible applications include printable transistors, logic and memory components, photovoltaic films, RFID tags, and OLEDs and displays, the company said.

May 31, 2006 – Universal Display Corp. (UDC) and Mitsubishi Chemical Corp. have agreed to codevelop materials for phosphorescent organic light-emitting diode (OLED) displays that are processable through solution, or “wet” processing methods, such as inkjet printing.

The technology, which promises high efficiency of phosphorescent technology with lower-cost inkjet printing techniques, is projected for use with large-area OLEDs, seen as a strong growth market in coming years.

Universal Display has developed a proprietary “PHOLED” phosphorescent OLED technology, which it claims offers up to 4x higher efficiency than conventional OLED technology. Late last year, Mitsubishi Chemical and Mitsubishi Chemical Group’s Science and Technology Research Center unveiled a printable high-efficiency blue phosphorescent OLED. Together, the companies aim to accelerate development of printable red, green, and blue phosphorescent materials.

“Collaborating with a world-class chemical company like Mitsubishi Chemical allows us to share ideas and help each other reach the next level of innovation for OLED materials based on our PHOLED phosphorescent OLED technology and Mitsubishi Chemical’s expertise in OLED chemicals and ink formulation,” stated Steven Abramson, president and COO of Universal Display.

May 17, 2006 – Scientists from the U. of Cincinnati claim to have developed a method to make organic light-emitting diodes (OLED) as much as 10x more efficient and 30x brighter — with a little help from the humble salmon fish.

Incorporating a thin layer of salmon DNA into the OLED structure as an electron-blocking layer improves the chance for electrons and holes to recombine and emit photons, thus enhancing the device’s luminance, the researchers claim. Tests showed that a green “BioLED” with the DNA electron blocking layer (current density of 200 mA/cm2) achieved luminance of 15000 cd/m2, vs. 4500 cd/m2 for conventional OLEDs. A similarly enhanced blue BioLED produced 1500 cd/m2 luminance, nearly twice as much as the baseline device.

“It turns out that DNA has nearly ideal energy levels that allow hole transport to proceed unimpeded while it prevents electrons being transported too quickly,” explained U. of Cincinnati researcher Andrew Steckl. The BioLEDs’ lifetime also appears to be significantly longer than that of equivalent OLEDs without the DNA layer — the team is still trying to understand the difference in degradation mechanisms. Also, Steckl said the team is working to introduce lumophores into the DNA layer to obtain combined photoemission from multiple layers in the device, and are exploring other types of DNA for OLED fabrication, including mammalian and plant DNA.

The water-soluble DNA was difficult to process into thin films, so the researchers utilized a surfactant to convert the DNA into a form insoluble with water, but soluble in selected alcohols. It was then spin-coated into a 20µm-thick electron blocking layer on top of the BioLED’s hole injection layer.

Should the process prove viable for production of OLEDs, availability of salmon DNA is another bonus. Salmon fishing is a 200,000 tons/year industry in Hokkaido, Japan, and normally the male roe is a waste product, but is very rich in DNA.

Full details of the process were published in the May 8 edition of the journal Applied Physics Letters.

April 14, 2006 – Novaled and Ciba Specialty Chemicals announced an industrial collaboration in the field of OLED materials. Ciba Specialty Chemicals will produce the organic dopant and transport materials developed by Novaled.

Ciba will produce the materials using its know how in the synthesis of organic materials, whereas Novaled will continue to market the materials. The two companies will also collaborate in the development of future OLED products and platforms based on Novaled’s technology and materials.

Oct. 20, 2005 — EV Group, an Austrian maker of nanotech tools, announced the sale of an EVG570 High Volume Hot Embossing System to NIL Fab Inc. of Canada.

NIL Fab is a nanoimprint lithography contract manufacturer that intends to prototype roadmap compliant, low cost analytical devices and other consumer related products.

NIL Fab’s Phase 1 facility is slated to offer prototyping services and low volume production for biosensors, lab-on-a-chip, optics and photonics, magnetic storage, OLEDs and other applications that make use of low cost nanoimprint lithography processes and materials. The fab was established by the Canadian NanoBusiness Alliance in partnership with the National Research Council of Canada.

August 3, 2005 – Universal Display Corp. has announced the demonstration of a white OLED lighting panel with a record power efficiency of 30 lumens per watt (lm/W) using the company’s PHOLED phosphorescent OLED technology at The International Society for Optical Engineering (SPIE) Symposia and Exhibition held in San Diego, CA.

The company’s white OLED performance is based on a novel panel design that consists of an array of red, green, and blue colored stripes. Adjusting the intensity of each primary color generates infinite shades of white color, typically characterized by color temperature and color rendering index.

Power efficiencies of this 6″ x 6″ prototype panel were measured at color temperatures between 2,900 and 5700K. The 30 lm/W white OLED power efficiency was achieved at a color temperature of 4000K, which is comparable to the color temperature and power efficiency of a cool fluorescent lamp. By comparison, typical incandescent light bulbs emit light at around 15-20 lm/W with a color temperature of 2900K.

This panel can also operate very brightly. For example, this 6″ x 6″ panel produced 150 lumens of optical power, at an efficiency of 15 lm/W and 3700K color temperature.

Increasing the efficiency of lighting by a small amount has the potential to generate tremendous savings in both cost and energy use.

This advance was reported in a paper, “Phosphorescent organic light-emitting devices for solid-state lighting,” presented at the SPIE Optics and Photonics 2005 Symposia, on Monday by Dr. Brian D’Andrade, senior scientist at Universal Display, at the San Diego Convention Center. This work was partially funded by a US Department of Energy Small Business Innovation Research grant.

April 22, 2005 — Litrex Corp., a Pleasanton, Calif., developer of inkjet systems for manufacturing next generation electronics and displays, announced it had shipped its 50th inkjet printer, a Generation 2, to an institute for developing a variety of LCD manufacturing applications.

The company’s inkjet printers are for precisely depositing an array of high-value materials, including electronic polymers, nano-metals, and biomaterials. The company says currently 25 companies worldwide are using them for materials deposition in industries such as OLED, organic semiconductors, and LCD manufacturing.

One of Litrex’s parent companies, Cambridge Display Technology (Nasdaq:OLED) develops light emitting polymers (P-OLEDs). Litrex’s other owner is ULVAC, Inc. (TOKYO:6728) of Japan, a leader in vacuum deposition for displays.