OLED - Technologie der Zukunft

Transcription

1 OLED - Technologie der Zukunft Dr. Manfred Weigand MERCK KGaA, Darmstadt, Germany Cleanzone 2014

2 Cathode Ray Tube (CRT) Source: Peter Littmann Source: Patrick Schindler Source: Bundesarchiv, Bild 183-H / CC-BY-SA 1967: Official start of color TV in Germany The tube was the dominating TV technology for many decades 2

3 Flat Panel Liquid Crystal Display Development >2010 Innovative Devices >2015 Displaying Futures Enabling and CRT replacement 3D TV Convergence of Lighting and Display Tablets Monitor TV Transparent Flexible, foldable Notebook Smartphones Window Displays Holography 3

4 LCD Technology dominates the display market 105 (266 cm) Mio pixels Source: LG Electronics Is there a chance for a new technology? 4

5 It s an OLED TV! OLEDs are LEDs : Light Emitting Diodes But they are made by organic materials: Organic Light Emitting Diodes OLED Source: LG Electronics Organic materials: - unlimited possibilities for molecule design - soluble and vaporable Great variety in processing 5

6 OLED Application Roadmap Source: Comedd Dresden > 2012 OLED TV and Tablet PC > 2010 Active Matrix OLED (smartphones) 6

7 Benefits of OLEDs displays: (compared to LCD display) Visibility: Better visibility from long distance Wider viewing angle Thickness: Down to 1.6 mm, like a piece of paper Image Quality: Faster response time Higher contrast (real black!) Extended color range Low Power Consumption: Used in Smartphones Still a challenge: Lifetime and costs 7

8 OLED TV Source: LG Electronics 8

9 The basic principle of an LCD (Liquid crystal display) 9 Off On

10 Color to the pixel Additive color mixture: Red + Green Yellow Red Green blue Color filters Liquid crystals TFT Array (on/off) on transparent ITO Permanent Backlight (LED) 10

11 The basic principle of an OLED display: Each OLED subpixel is a small lamp No backlight No polarization filter No color filter No liquid crystal layer 11

12 OLED How it works Substrat = Glas, Polymer Transparent Anode = ITO Emission layer (Organic Semiconductor) 3-6 Volt Cathode = Metal. Ba, Li, Mg Encapsulation 12

13 Typical OLED Stack Hole injection layer 13

14 OLEDs are very sensitive to moisture and air An extremly good encapsulation is necessary to avoid corrosion of cathode and to protect sensitive OLED layers Encapsulation Metal Cathode Organic Semiconductor transparent Anode = ITO Substrate Water Vapor Transmission Rate (WVTR): The target number is 10-6 (g/m2/day) 14

15 How good should the barrier be? ~100m Packaging Film Electronic grade (PET) ~50m Imagine a protective film covering the football field. How much water will pass through over ONE MONTH? 15

16 The answer is it depends on the film! Raw Film Food Packaging Photovoltaics OLED Packaging Film Electronic grade (PET) Schematic and idea from PETEC. Source: IDTechEx Less than a drop per month 16

17 Reduce Costs! 55 curved OLED TV 3D: Market price EURO 55 Liquid crystal TV 3D: Market price 800 EURO A main cost driver: Material deposition on mask in PVD process 17

18 Ink jet printing - an alternative to PVD 18

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20 Printing a sub pixel View from above 10 µm µm View from the side 3 7 printed layers Total nm 20

21 Final target: Less than 1 visible defect per panel Sources: LG Electronics The ink jet printing technology requires very high purity soluble OLED materials 21

22 Clean Zone Local working environment for ink jet printer requires ISO 3 (class1) (Standard in all display fabs, where wet substrates are handled, eg photo resist) Majority of particles come from the printer environment Only a small part of defects are caused by particles in the ink In PVD vacuum systems, a lot of effort is taken to avoid particles which may fall on the substrates during handling or operation. In OLED vapor additional care has to be taken to avoid dust stemming from the OLED material used. Here especially the powder form as well as the electrostatic discharge behavior is essential. 22

23 OLED beyond display: Lighting up the future One single big pixel is a lamp! Source: Manfred Weigand Soft,natural OLED light Bendable and ultra thin Source: Martina Hüber Car rear light Concept study by Philips Freedom of design Transparent 23

24 Summary OLED is a new technology for displays and lighting Great progress has been made in recent months and years to improve performance Reducing costs and improving lifetime are main challenges Printing displays and lighting has the potential to reduce costs 24

25 Merck OLED R&D Sites and Teams R&D centre in Germany, England, Korea, Japan Teams in Japan, Korea, USA, Taiwan & China Continuous investments 25 Global Concept including Local Support to Customers

26 Thank you for your attention Special thanks to Volker Hilarius and Edgar Böhm 26