OLED Displacing LCD, But Not Affecting Industry Leaders

By Michael P.C. Watts
One of the most common themes in high tech is how companies fail to deal with game-changing new products. Think about Kodak and digital cameras, Sony and the flash memory music player, Microsoft and the tablet, GE and Osram and the Light Emitting Diode (LED). The overwhelming conclusion seems to be that you have to be committed to making your own most valuable product redundant to survive.

The flat panel display business has coalesced around Samsung and LG, dominated by the two companies that can manage the massive infrastructure required to process glass that is more than 2.5 meters on a side. The guys with the manufacturing expertise are leading the way to make their existing capacity redundant, a lesson in how to deal with next-generation revolutionary technology. The dominant Liquid Crystal flat panel Display (LCD) manufacturers, Samsung and LG Electronics, seem to have decided to lead the way in commercializing OLED displays. In particular, Samsung is leveraging vertical integration to lead the way in using OLEDs in its own cell phone displays.

The news from the SID Display Conference is all about the rapid insertion of OLEDs into displays, from Google glasses, to cell phones and TVs. Early insertion has started with applications for smaller displays in devices with limited life expectancy, such as cell phones. The applications such as household lighting have the longest life expectancy and will be the last and most lucrative insertion.

The efficiency of OLEDs at better than 100 lm per watt are now comparable to (inorganic) LEDs. The underlying electronic band structure of organic and inorganic LED’s are similar; semiconductor regions to make ohmic contact between conductor, regions to transport electrons or holes to the emitting or active layer, regions to block the flow of the opposite charge, and the active region. The different semiconductor regions in Inorganic LEDs are constructed by changing the composition and doping level of the semiconductor during the chemical vapor epitaxy growth. The bad news is that the growth is slow and “hetero-epitaxial,” which requires a crystalline substrate. The good news is that an individual LED is so small that it can be a cost-efficient light source.

The different semiconductor regions in organic LEDs are constructed of different organic molecules, which are patterned quickly by shadow masking during “non–epitaxial” vapor deposition. This makes them ideal for building diodes on glass for displays.

The most interesting story is the impact of consolidation on the development of OLEDs—improved power efficiency, thickness, flexibility, and contrast. In fact, OLEDs are poised to replaced LCDs. Samsung estimates 40% of TVs will be OLED by 2017. Samsung and LG have chosen different routes to make this happen. LG is using a white OLED with color filters, whereas Samsung is using separate RGB emitters.

Samsung appear to be taking a best-of-breed strategy by partnering with different suppliers for the different materials in each semiconductor layer. As best I can make out, Novaled supplies the transport and blocking layers; phosphorescent emitters come from Duksan Hi-Metal for the blue, and Universal Display Corp. for the red and green emitting materials.

Other players are trying to get in on the opportunity, as well. Dupont announced a $30M facility to build an ink-jettable OLED display. Panasonic announced a record efficiency with patterned substrates for improved light extraction. But just to put things in perspective, Samsung’s investment in OLEDs was $6B in 2012, with $25M spent on a U.S. patent operation alone!

The even longer term opportunity are in OLEDs for general lighting. Today’s efficiencies are competitive, but they need further improvements in lifetime to get from TVs to light bulbs. The bottom line: Leadership in OLEDs is a planet-wide opportunity.

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