OLED ink jet printing: introduction and market status - Page 23

The Holst Centre and imec announced a new high-resolution flexible OLED displays research program. This new program builds on the existing research fields such Organic and Oxide Transistors and Flexible OLED lighting. The new program aims to develop an economically scalable route to flexible AMOLED mass production, facing challenges such as high resolution, low power consumption, large area, outdoor readability, flexibility and light weight.

The partners will develop a mechanically flexible encapsulation film and TFT backplane, a printed high-efficiency OLED, new materials and processes that will allow cheaper production at better quality and driver design. They will also develop a new manufacturing equipment such as fine patterning equipment for backplanes and tools for integrated roll-to-roll manufacturing. This new program follows up on the FLAME project. Above you can see a prototype Polymer-Vision made flexible OLED made together with imec and the Holst Center.

Aneeve Nanotechnologies, a startup company at UCLA's on-campus technology incubator, managed to fabricate a new fully ink-jet printed carbon nanotube (CNT) circuit that is used to drive OLED displays. The company says that this is the first practical demonstration of carbon nanotubebased printed circuits for display backplane applications, and it shows significant performance advantages over traditional organic-based printed electronics.

Aneeve says that this shows that CNT is a viable technology to compete with a-Si and metal-oxide semiconductor for low-cost and scalable backplanes.

Peter Misek, an analyst at Jefferies says that he believes that Apple decided to buy iPad 3, iPhone 5 and TV display panels from Sharp. At first these will be IGZO based LCDs - which will be brighter, clearer, thinner and more efficient than existing LCDs. But Misek also believes that Sharp and Apple will jointly develop OLED displays (probably IGZO based as well) within 1-2 years which will be used in future iPhone and iPad generations. OLED TV panels aren't expected until 2015.

Misek says that the two companies are working towards a new printing technology for producing these small/medium OLED panels - and that a pilot line will be in place by middle 2012 for testing purposes. Full production will be possible in 2013. The new technology, according to Misek, is a combination of inkjet printing and a daisy wheel. The daisy wheel is an impact printing technology and I'm not sure how it relates to OLEDs.

A few weeks ago we reported that Sumitomo Chemical began construction of a PLED material factory (which will be operational in 2012) in a several billion yen investment. These materials are aimed towards large panel (OLED TV) production. Today we have a new report that say that Sumitomo made a breakthrough in its PLED material technology - which will eventually enable production cost to be slashed by up to 50% (compared to SM-OLED based displays).

Sumitomo 6.5-inch AMOLED prototype

The annual output of their new Osaka plant will be enough to produce 4-5 million 40" OLED TVs. Sumitomo plans to offer these materials to TV makers in Japan, South Korea, and Taiwan. PLEDs (or Polymer-OLEDs, sometimes called PLED too) are OLED devices made from polymer (large-molecules) materials and are more easily adapted for printing (solution-processable) compared to Small-Molecule OLEDS (SM-OLEDs). Some companies believe that PLEDs are the best way to create large OLED panels using printing methods. You can read more about PLEDs here.

HP has developed a new method to produce large AMOLED panels, based on roll-to-roll manufacturing. They say that one of the biggest challenges to make flexible OLEDs is the alignment on large area flexible substrates. The new solution uses self-aligned imprint lithography (SAIL) to laminate a well-defined micro OLED (µOLED) frontplane unto a flexible active matrix amorphous silicon TFT backplane.

SAIL process flow

HP says they already built a proof-of-concept AMOLED device - which contains a flexible µOLED frontplane with OLED sizes of 50 µm on PET and active matrix backplane on polyimide with pixel pitches of 1 mm. The company claims that the new method will enable large area OLEDs at a very low cost.

There are reports that Seiko Epson and Tokyo Electron are planning to launch an OLED TV production project, in a ¥2-3 billion ($20-40 million) investment. The companies are still considering several options for this plant, but apparently they want to begin installing equipment sometime in 2013, with "full scale mass production" in 2013. This seems a very small investment, so we're not sure if this is indeed mass production or just a pilot line.

Espon 14-inch Inkjet processed OLED

The reports says that this will be a 6-Gen plant. Tokyo Electron and Seiko Epson announced their plans to co-develop OLED TV printing technology back in November 2010.

SouthWest NanoTechnologies (SWeNT), a US company that produces single-wall and specialty multi-wall carbon nanotubes has been awarded a two-year, $500,000 grant from the Oklahoma Center for the Advancement of Science and Technology (OCAST) to develop semiconducting inks, based on its single-wall carbon nanotube (SWCNT) technology, suitable for printing thin film transistors (TFTs).

According to SWeNT's CEO, Dave Arther, the company will leverage its current NIST-TIP grant program to produce semiconductor grade SWCNTs, which will be converted into printable inks using proprietary V2V™ ink technology. The company's inks overcome two market barriers, commercial availability and compatibility with standard printing equipment.

Sony is showing a new hybrid-printed OLED device. The red and green OLEDs are printed while the blue OLED is apparently vacuum deposited. The prototype on display is a full color 3", VGA (640x480) resolution (270 ppi).

Dupont has unveiled two new OLED display prototypes made by a coating process (using solution processable materials). The first (shown below) is a 4.3" 480x272 (128 ppi) and the second is a 5.8" display offering 294x196 (83 ppi).

Dupont says that the solution-processable displays offer better uniformity than commercial LCD displays. The cost advantage for solution-processable OLEDs grow as as the panel size increases.

Universal Display has quietly released a new PHOLED material performance chart. Their Green-Yellow material now has 1.4 million lifetime hours (LT50), and their Red color offers 900,000 hours. Blue is still very challenging, and their light blue offers only 20,000 hours (LT50). Here's the complete chart:

The company also released some PHOLED material efficiency. Using only red PHOLED (with green and blue fluorescent materials) will result in a display that is about 15% more efficient compared to an LCD (this is the combination Samsung used in their 4.5-Gen AMOLED fab). Adding green color will result in a a display that is 30% more efficient compared to an LCD (this is the combination Samsung is using in their new 5.5-Gen fab). Adding blue will give a 50% more efficient display. UDC says that further enhancements (not specified) can result in a display that is 67% more efficient than an LCD. All these results are based on a 4" display operating at 300 cd/m² showing a video that has 40% pixels on.