Organic Light-Emittin g Devices

Size: px

Start display at page:

Download "Organic Light-Emittin g Devices"

Silas Brooks
5 years ago
Views:

1 Joseph Shinar Organic Light-Emittin g Devices A Survey

3 Preface Contributors v xv 1 Introduction to Organic Light-Emitting Device s Joseph Shinar and Vadim Savvateev Introduction Basic Electronic Structure and Dynamics of rr-conjugated Materials Basic Structure of OLEDs OLED Fabrication Procedures Thermal Vacuum Evaporation Wet-Coating Techniques Materials for OLEDs & PLEDs Anode Materials and HTLs or Buffers Small Electron-Transporting and Emitting Molecules Small Molecular Guest Dye Emitters White OLEDs Phosphorescent Small Molecules & Electrophosphorescent OLEDs Fluorescent Polymers Cathode & Organic/Cathode Buffer Materials Basic Operation of OLEDs Carrier Transport in OLEDs Polaron vs Disorder Models for Carrier Hopping 24

4 1.7.2 Long-Range Correlations Carrier Injection Space-Charge Limited Versus Injection-Limited Current Mechanisms The Efficiency of OLEDs Degradation Mechanisms Outlook'for OLEDs 3 3 References 34 2 Molecular LED : Design Concept of Molecular Materials fo r High-Performance OLED Chihaya Adachi and Tetsuo Tsutsui Introduction OLED Development from the 1960s to the 1980s Working Mechanisms of OLED Charge Carrier Injection and Transport Carrier Recombination and Emission Process Estimation of External and Internal Quantu m Efficiency Design of Multilayer Structures Molecular Materials for OLED Hole-Transport Material Electron-Transport Material Emitter Material Dopant Material Molecular Tuning for High EL Efficiency Molecular Tuning for a High EL Durable OLED Future Possibilities of OLED Conclusion 65 References 65 3 Chemical Degradation and Physical Aging of Aluminum(III ) 8-Hydroxyquinoline : Implications for Organic Light-Emittin g Diodes and Materials Design Keith A. Higginson, D. Laurence Thomsen III, Baocheng Yang, an d Fotios Papadimitrakopoulos Introduction Chemical Stability of OLED Materials Thermal Hydrolysis of Alq Electrochemical Degradation of Alq 3 and Hq Morphological Stability of Organic Glasses in LEDs Crystallization of Alga Guidelines for Amorphous Materials Selection Crystallization and Aging of AlMq3 an d Alq 3/AlMq 3 blends 91

5 3.4 The Effect of Aging Processes on OLED Performance 9 5 References Organic Microcavity Light-Emitting Diode s Ananth Dodabalapur Introduction Types of Microcavities Planar M crocavity LEDs Single Mode and Multimode Planar Microcavity LEDs Intensity and Angular Dependence in Planar Microcavities Materials for Organic Microcavity LED Displays Summary 12 3 References Light-Emitting Diodes Based on Poly(p-phenylenevinylene ) and Its Derivatives Neil C. Greenham and Richard H. Friend Introduction The Electronic Structure of PPV Synthesis of PPV and Derivatives Single-Layer LEDs Multiple-Layer Polymer LEDs Transport and Recombination in Polymer LEDs Optical Properties of Polymer LEDs Novel LED Structures Prospects for Applications of PPV-Based LEDs Conclusions 15 0 References Polymer Morphology and Device Performance i n Polymer Electronic s Yijian Shi, Jie Liu, and Yang Yang Introduction The Control of Polymer Morphology The Polymer-Polymer Interactions in Solutions The Morphology Control of Polymer Thin Films vi a the Spin-Coating Process The Control of Device Performance via Morphology Control Conductivity of the Polymer Film Charge-Injection Energy Barriers The Turn-on Voltages The Emission Spectrum of the Device The Device Quantum Efficiency Conclusions The Solvation Effect and Polymer Aggregation 182

6 6.4.2 The Device Emission Color and the Quantu m Efficiency The Conductivity of the Film The Turn-on Voltage of the PLED Device 18 3 References On the Origin of Double Light Spikes from Polymer Light-Emittin g Devices Aharon Yakimov, Vadim Savvateev, and Dan Davidov Introduction Experimental Results and Analysis Discussion Conclusions 20 2 References Electroluminescence with Poly(para-phenylenes ) Stefan Tasch, Wilhelm Graupner, and Gunther Leising Introduction Physical Properties of Oligophenyls and Polyphenyls Processing and Stability Geometric Arrangement of Para-phenylenes Absorption Properties Emission Properties Excited States Charge Transport Electroluminescence Single-Layer LED Based on PPP-Type Polymers Emission Colors LEDs Based on Multilayer Structures LEDs Based on Polymer Blends Light-Emitting Electrochemical Cells Based on PPPs Conclusions 23 8 References Direct and Alternating Current Light-Emitting Devices Based o n Pyridine-Containing Conjugated Polymers Y. Z. Wang, D. D. Gebler, and A. J. Epstein Introduction Experiments Results and Discussion Summary and Conclusion 26 1 References 262

7 10 Polyfluorene Electroluminescence Paul A. Lane Introduction Synthesis and Characterization of Polyfluorene Polyfluorene Synthesis Optical and Physical Characterization Electronic Characterization Electroluminescence Polyfluorene Electroluminescence Fluorene-Based Copolymers Doped Polyfluorene Light-Emitting Diodes Concluding Remarks 29 8 References 29 9 Index 303

Organic Light-Emitting Devices

Organic Light-Emitting Devices SPRINGER SCIENCE+BUSINESS MEDIA, LLC Joseph Shinar Editor Organic Light-Emitting Devices A Survey With 158 Illustrations AlP ffi. Springer Joseph Shinar Ames Laboratory USDOE