Solution based OLEDs - Page 20

UDC announced today that it has been awarded a significant patent covering ink-jet printing of phosphorescent OLED displays, US Patent No. 6,982,179, titled "Structure and Method of Fabricating Organic Devices".

"This PHOLED ink-jet printing patent provides another option for OLED manufacturers in choosing how to produce displays using our proprietary phosphorescent OLED technology," said Steven V. Abramson, President and Chief Operating Officer of Universal Display Corporation. "The patent is a further demonstration of the breadth and depth of Universal Display's PHOLED technology, which is widely recognized as critical for OLED displays - from small, where power efficiency is critical, to large, where power efficiency equates to less heat generation."

Mitsubishi Chemical today announced that it has developed an Organic Light-Emitting Diode device with the highest efficiency in the world in its new blue phosphorescence OLED material.

The new OLED material, which can be produced by a lower-cost, wet-coating process, is expected to open the way to the development of a new class of large flat-panel displays.

The newly developed OLED device employs MCC's own blue phosphorescence host material (wet-coating type), hole blocking material, and hole injection material to optimize the design of a device to achieve the current efficiency of 30 cd/A at the intensity of 100 cd/m2 (external quantum efficiency: 13%), more than twice that of conventional blue wet-coating type OLEDs.

Cambridge Display Technology (CDT) has announced another important step in the development of polymer light emitting diode (P-OLED) display technology with the production of a number of 14 inch full color displays using ink jet printing.

The displays were produced at CDT's Technology Development Centre in the UK, and feature a resolution of 1280 x 768 pixels x RGB, equivalent to almost three million sub-pixels, or over 30 million ink jet drops.The active matrix panels use an amorphous silicon backplane, and were made using a multi-nozzle approach - up to 128 nozzles - with no interlacing, and are believed to be the first of their kind ever produced.

Litrex Corporation has shipped the first M-Series(TM) Inkjet Systems to a leading display maker. These systems reinforce Litrex Corporation's position as the world leader in inkjet manufacturing systems for display applications. These new "next generation" M-Series(TM) tools build upon the success of over 50 inkjet systems that Litrex Corporation has installed worldwide at 25 customer sites.
The M-Series(TM) Inkjet Systems are built for substrates from Gen 3 to Gen 7 size, and are designed for precise deposition of high value materials such as those in P-OLED, LCD, nano-metals and biomaterials. The M-Series(TM) Inkjet Systems have a modular architecture that builds upon Litrex Corporation's existing experience and allows new equipment to be designed and adapted quickly to other applications.

The U.S. Display Consortium (USDC) has awarded a research and development contract to Dow Corning Corp. to develop hole injection materials for producing higher efficiency OLED suited for high-definition displays.

USDC and Dow Corning will equally share the cost of the $2.39 million development project.
The USDC-funded project will be undertaken in two phases, with the second phase focused on the application of Dow Corning's hole injection materials using inkjet printing or other patterning techniques.

Litrex Corporation shipped its milestone 50th inkjet printer, a Generation 2, to a major institute for developing a wide variety of LCD manufacturing applications. This shipment solidifies Litrex's leadership in the development of inkjet printing systems for new electronics manufacturing applications. Litrex's current printers are the most advanced inkjet systems for precisely depositing an array of high-value materials, including electronic polymers, nano-metals, and biomaterials. Currently 25 companies worldwide are utilizing Litrex printers for materials deposition in industries such as OLED, organic semiconductors, and LCD manufacturing.

The new facility has been established at Hsin-Chu with the delivery of three Litrex 142P ink jet printers. The Litrex printers are robust, production-capable units, with the ability to print 370 x 470mm glass substrates at approximately two to five minute intervals, and these have been commissioned with the support of CDT’ s Field Support Engineers based in the region.

When combined with the process technology now being developed at CDT and transferred to Delta engineers as part of the commercial transaction, the facility will pave the way for Delta-Opto’s full-scale production of colour displays.

Among the patents now allowed in the US is a patent relating to OLEDs which comprise hole transport, electron transport and emissive components, using type II interfaces, contained in the same molecule. This is believed to be of considerable importance in the context of the printing of OLED devices. Molecules containing 'type II' interfaces are believed to be important in achieving high efficiency display devices.

Other new US patents allowed include a patent relating to the use of a dielectric barrier layer over the key emissive layer to protect it from damage due to sputtering of a conductive layer. This is expected to have important application in top emitting devices in which the light does not have to pass between the transistors but, more efficiently, through a transparent cathode structure.

Cambridge Display Technology (CDT) and Add-Vision Inc (AVI), a pioneering developer of technology for low information content displays, have announced a business collaboration in which CDT will give AVI a paid-up license to certain CDT IP for specialized low resolution display applications. CDT will also join the existing private equity investors in a new round of funding to allow AVI to develop the technology more rapidly. In return for the license and equity investment, CDT will acquire a very substantial minority position in AVI.

The Add-Vision approach, developed over the last ten years, allows simple PLED displays and backlights to be fabricated by fast screen printing on plastic substrates without the need for expensive clean room facilities. As a result, the cost of display production can be kept lower, while maximizing throughput volumes.

Toppan Printing and Cambridge Display Technology (CDT) have just announced the commencement of Phase Two of their joint programme to explore alternative printing processes for the fabrication of displays based on PLED technology.

Phase One, completed at the end of 2004, concentrated on proving the feasibility of using a roll printing process to deposit light emitting polymer materials onto a glass substrate.