Margreet de Kok - Holst Centre

Margreet de Kok - Holst Centre

• 2.
  November 27, 2012 SmartMaterials for Conformable Electronics and Photonics Margreet de Kok Holst Centre Mikrocentrum 23 november 2012
• 3.
  10 november 2011 Presentation overview Contents 1. Holst Centre 2. Introduction OLED 3. Application of OLED 4. Lifetime of OLEDs 5. Conformable technology 6. Conclusions
• 4.
  © Holst Centre 4 Holst Centre Fingerprint Who we are Independent research organization co-founded by IMEC (1300 fte, Belgium) and TNO (4500 fte, the Netherlands) in 2005 Global network of industrial and academic partners 150 researchers and 60 resident researchers from industry and university What we do Creating generic technologies, time to market 3..10 years Research Focus on wireless, autonomous micro-systems and flexible electronics How we work Open Innovation through precompetitive research programs Roadmaps defined along with partners Day to day interaction with industrial residents Results are shared between partners
• 5.
  © Holst Centre 5 Large Area Electronics market applications Flexible displays Plastic solar cells Touch screens Plastic batteries Smart packaging Signage RFID tags OLEDs Sensors Disposable bio-sensors Smart bandage Electronic textiles
• 6.
  © Holst Centre 6 Important Enabler: Organic Semiconductors New ways of MicroDrop processing Inkjet printing Soluble Semiconductors Roll to Roll coating
• 7.
  © Holst Centre 7 Access to Unique Set of Infrastructures and Process Labs High Tech Campus, Eindhoven Amsterdam Netherlands Eindhoven Düsseldorf Aachen Leuven Belgium
• 8.
  © Holst Centre Industrialpartners from across the value chain
• 9.
  10 november 2011 Contents 1.HolstCentre 2.Introduction OLED 3.Application of OLED 4.Lifetime of OLEDs 5.Conformable technology 6.Conclusions
• 10.
  © Holst Centre 10 OLED Basics Two types of OLEDs: cathode Organic layers anode Polymer LED Small molecule LED
• 11.
  © Holst Centre 11 OLED: Electroluminescence (Fluorescent emitter) Typical Light Emitting Polymers: PPV (polyphenylene vinylene) PF (polyfluorene)
• 12.
  © Holst Centre 12 OLED: Injection scheme SrO BaO Cs LiF GdB6 2 Ba Li,K Work function (eV) Ca TiN 3 Mg Hf 4 In 4 Al Ag 5 PEDOTNi Au ITO Pt Se TiO 6 2 High workfunction Low workfunction anode materials cathode materials
• 13.
  © Holst Centre 13 IVL • Vbi ~Vturnon 10000 BL102 • Dependent on band gap material 1000 • Dependent on work function 100 10 difference of the contacts J (A/m ) 2 1 0.1 • Blue and white 20- 50 lum/W 0.01 1E-3 • Record: 100 lum/W 1E-4 -2 0 2 4 6 8 Bias (V) 2 BL102 Ba/Al LUMOPF (2.2 eV) (2.7 eV) PEDOT: Efficacy (lm/W) PSS 1 (5.1 eV) HOMOHT (5.2 eV) 0 -2 0 2 4 6 8 Energies with respect to the vacuum Bias (V) level
• 14.
  © Holst Centre 14 Application in OLED 144 cm2 white PLED without ITO using high conductivity PEDOT with Ag printed shunting lines AGFA
• 15.
  10 november 2011 Contents 1.HolstCentre 2.Introduction OLED 3.Application of OLED 4.Lifetime of OLEDs 5.Conformable technology 6.Conclusions
• 16.
  © Holst Centre 16 OLED Applications & Expectations Signaling Signage Lighting Displays
• 17.
  © Holst Centre 17 But also: Company logo Automotive Healthcare Add-Vision Advertising Automotive
• 18.
  © Holst Centre 18 Flexible OLEDs • Only prototypes, no commercial products Add-Vision Sony Samsung Novaled/Assilor-Mital UDC GE • Showstopper: barrier films
• 19.
  © Holst Centre 19 Next Application for OLED: Solid State Lighting LED (SM/P)OLED
• 20.
  © Holst Centre 20 Solid State Lighting Small-molecular Inorganic Organic Macromolecular OSRAM
• 21.
  © Holst Centre 21 Comparison Inorganic – Organic LEDs • Inorganic LEDs • Organic LEDs • Products on the market with • First lighting products on high efficiency and long the market lifetime • Large area possible and • Small area and high therefore low luminance luminance (no large area enough possible) • Thin • Thermal management needs • Thermal management less attention problematic • (Colour stability of • Colour better controllable production leads to binning • Cost per area effective of LEDs) Application and design freedom (and price) make the difference
• 22.
  © Holst Centre 22 Organic light sources and detectors: opportunities and challenges • Form freedom • Large area possible • Flexibility (bendability) • Very thin features • Fine tuning of optical properties possible • Integration with multiple functionalities possible in foil • Production technology versatile • Cost aspect positive • Challenges: • Processing thin layers - shorts • Encapsulation and intrinsic lifetime • Efficiency • Current density distribution • Design of combination of building blocks
• 23.
  © Holst Centre 23 Why flexible? • Enhanced functionality for the end user: bendable, rollable devices But also • Integration of foil devices in products & systems: conformal application?; convenient feeding into assembly system • Efficient large area production of foil devices (e.g. roll-to-roll; no manual assembly) -> cost aspect Source: GE Source: Metsuo
• 24.
  © Holst Centre 24 State-of-the-art in white OLED
• 25.
  © Holst Centre 25 OLED Trends Materials Substrates: flexible plastic or metal substrates combined with R2R processing Barrier: strong focus on developing flexible thin film barriers (Holst Centre, Vitex, General Electrics, Dow, ..) with WVTR < 10-6 g/m2.day Emitters: phosphorescent emitters (UDC, Sumation, Merck, Novaled, ..) Transport layers: doping of transport layers (Novaled, ..) Cathodes: top emitting/transparent OLEDs with transparent cathodes Anodes: high conductive organic materials and/or or introduction of support structures (evaporated or other) (GE, OLLA, Holst Centre, ..) Processing: Roll-to-roll processing on flexible plastic or metallic substrates Printing or coating of functional materials in general (as opposed to spin-coating) Printing or coating of small molecules (Dupont, UDC, ..) Devices: Innovative OLED designs / Intelligent Lighting >100 cm2 lighting tiles (Lumiotec, GE, Philips, OSRAM, UDC, Konica Minolta, ..) OLED display driving: AMOLED as opposed to PMOLED (SDI, LGE, SONY, ..) TFT towards oxide TFT as opposed to OTFT / LTPS (Dai Nippon Printing) Place-it: conformable electronic systems comprising OLEDs
• 26.
  10 november 2011 Contents 1.HolstCentre 2.Introduction OLED 3.Application of OLED 4.Lifetime of OLEDs 5.Conformable technology 6.Conclusions
• 27.
  © Holst Centre 27 OLED Degradation
• 28.
  © Holst Centre 28 OLED Degradation
• 29.
  © Holst Centre 29 OLED Degradation: black spots • Intrinsic: homogeneous degradation • Cathode oxidation: local degradation leading to black spots H2O, not O2 Right after processing ~10h at 20 °C / 50% RH
• 30.
  © Holst Centre 30 Standard Encapsulation State-of-the-art encapsulation using metal or glass lid with cavity containing getters no hermetic seal (getter!) 40,000 hrs at 80 °C without black spot formation cathode getter organics ITO substrate But, it is not applicable for: Fast production Large area devices Flexible (foil-based) devices
• 31.
  © Holst Centre 31 Requirements for (TF) barrier/encapsulation • Intrinsic WVTR < 10-6 g.m-2.day-1 • No black spots >5 years @ 20/50 >504 h @ 60/90 • Feasibility for R2R Barriers should be rollable over d=20cm • Low cost High deposition rates Barrier on foil specific: • Transparency for visible light >90% • Uniform light output Extremely uniform layers over large areas • Light outcoupling • Abrasion resistance, UV protection, etc.
• 32.
  © Holst Centre 32 Multilayer approach • Stacks of inorganic and organic layer used to decouple pinholes and get full coverage => time delay of black spot formation • Holst approach: SiN – OCP – SiN • OCP = organic coating for planarisation 100 SiN SiN-org-SiN planarization black spot area (a.u.) 10 4 layer 3 1 1 2 0.1 10 100 1000 10000 time (hrs)
• 33.
  © Holst Centre 33 State of the Art for encapsulation • Wvtr: 10-6 g/m2day • >5000 hrs at 20/50 black spot free and still running Side leakage Black spots by pin holes
• 34.
  © Holst Centre 34 Advanced systems by combined functionalities in Foil • Organic LEDs • Organic Photodetectors • Organic Photovoltaics • Embedded circuitry • Embedded chips • RFID • Memories • Sensors Electrochemical Optochemical Optical
• 35.
  © Holst Centre 35 35 Device Design - laminated foil approach • Foil Double side processing Modular: diodes and LEDs printed on separate foils • Top emissive PLEDs, Bottom receptive OPDs: Photodiode skin LED • Bottom emissive PLEDs, Top receptive OPDs: skin 30 Spectral Radiance (10 W/sr m nm) 2 25 20 -3 • Etc. 15 10 5 0 500 550 600 650 700 750 wavelength (nm)
• 36.
  © Holst Centre 36 36 Printed devices • Foil Single side processing Diodes and OLEDs via printing Arrays of different devices on one substrate
• 37.
  © Holst Centre 37 37 Foil Integration • Modular approach • Distribute functions over different layers µ-via technology combined with lamination • Silicon in Foil embedding
• 38.
  © Holst Centre 38 38 First Organic Device Prototype: Proof of Principle • OPD • Works! Total measured current PPG comparable to commercial ca. 10 µA pulse-oximeter (Nelcor N200) Signal ca. 50 nA • PLED I = 80 mA/cm2 V = 5.2 V L = 520 Cd/m2 Signal (a.u.) Organic Nelcor N200 0 1 2 3 4 5 Time (s)
• 39.
  10 november 2011 Contents 1.HolstCentre 2.Introduction OLED 3.Application of OLED 4.Lifetime of OLEDs 5.Conformable technology 6.Conclusions
• 40.
  © Holst Centre 40 Rigid –> flexible -> conformable Glass based OLED Flexible OLED Philips Lighting Holst Centre
• 41.
  © Holst Centre Thevision: conformable electronic and photonic systems • Featuring Conformable, stretchable/flexible Thin and light weight Unobtrusive integration Wearable • Applications: Biomedical (sensors, phototherapy) Textile/fashion, Outdoor (biking, road safety) Architecture Displays Interior design (curtains, furniture) • Advantages organics c.t. inorganics: Large area: homogeneity Very thin Temperature management Combination inspiring Margreet de Kok Holst Centre 2011 august SPIE 41
• 42.
  © Holst Centre Applications for wearable electronics & photonics furniture conformable foil – textile technology Camouflage for defense Light therapy Safety on the road Textile for fashion and safety 42
• 43.
  © Holst Centre 43 Healing power of sunlight: wearable phototherapy TBC treatment by sun therapy
• 44.
  © Holst Centre 44 Example - jaundice treatment of neonatals • Old treatment Static light sources necessitating eye protection of neonatal Jaundice treatment: photochemical conversion and excretion of bilirubine (yellow colour treatment) • New possibility Wearable light source less interfering with care including bonding with parents Philips BilitXTM Source flickr: 1542122226_5e43a1d008 and 2538039854_e67b67926c Blue LED based
• 45.
  © Holst Centre 45 Other options for applications • Light in safety (traffic, working conditions) • Light harvesting (tents, outdoor sports, clothing) • Phototherapy: psoriasis, eczema, jaundice, wound healing, prevention decubitus, pain relief, skin rejuvenation • Camouflage • Textile design – fashion! • Bring light where no light was before
• 46.
  © Holst Centre Conformabilityby segmented approach 46
• 47.
  © Holst Centre 47 Conformable electronics T. Sekitani, T. Someya et al. Nature Materials 8, 2009 p. 494-499 R. Kim, J. Rogers, et al. Nature Materials 9, 2010, p. 929-937
• 48.
  © Holst Centre 48 Stretchable systems • OLED structuring on rigid regions: printing technology • OLED / OPV need protection by barrier technology • Interspaces deliver stretchability and should contain electric circuitry: Ag nanoparticles in binder matrix pedot LEP Ba/Al foil anode cathode pedot Ba/Al Top barrier Bottom barrier foil anode cathode
• 49.
  © Holst Centre 49 Structured deposition of active materials • Printing: Inkjetable ink formulation (halogen-free solvent): droplet formation Jetting and stable in time & speed Ink & substrate interaction Layer formation and homogeneity Device performance and efficiency
• 50.
  © Holst Centre 50 Ink & substrate interaction • Pinning and de-wetting Plasma treatment Temperature treatment
• 51.
  © Holst Centre 51 Solvents selective layer formation A 100% A:B=50:50 B 100%
• 52.
  © Holst Centre 52 Inkjet printed OLED active layer development 2007 2011
• 53.
  © Holst Centre 53 State of the art
• 54.
  © Holst Centre Levelof integration into textile for wearable systems • Textile: In textile as fiber Onto textile by conductive yarns to electronics Iron on self contained system Fibers Fabrics Product 54
• 55.
  © Holst Centre CIMTEC2012 M. de Kok 55
• 56.
  © Holst Centre 56 Stencil printing of ICA
• 57.
  © Holst Centre 57 Bonded OLED onto textile
• 58.
  © Holst Centre Foilcomponents on textile 58
• 59.
  © Holst Centre Stretchablesystems in rubber (meander) • Light homogeneity • Bare die for reduced thickness • Density of elements • Thermal management Frederick Bossuyt Holst Centre / imec Gent 59
• 60.
  © Holst Centre 60 Platform for Large Area Conformable Electronics by InTegration FP7 Place-it 60
• 61.
  10 november 2011 Contents 1.HolstCentre 2.Introduction OLED 3.Application of OLED 4.Lifetime of OLEDs 5.Conformable technology 6.Conclusions
• 62.
  © Holst Centre 62 Conclusions • Organic electronics on textile have a bright future • Technology development indispensable • Collaboration between disciplines necessary • Conformable electronics will change the world • Margreet.dekok@tno.nl • www.holstcentre.com • Thank you for your attention
• 63.
  Visit us at www.holstcentre.com