有机光电半导体材料及其未来之应用.ppt

有機光電半導體材料及其未來之應用,Institute of Electro-Optical Science and Engineering, National Cheng Kung University, Tainan, Taiwan 701 成功大學 光電科學與工程研究所 01/16/2007,郭 宗 枋 助理教授,T.-F. Guo,NCKU Institite of Electro-Optical Science & Engineering,2,Outlines,Semiconductors Organic semiconductors (energy and delocalization of charge carriers) OLEDs and PLEDs 基礎原理和應用 Organnic photovoltaic and solar cells Conclusions,T.-F. Guo,NCKU Institite of Electro-Optical Science & Engineering,3,Fundamental science of inorganic semiconductors,T.-F. Guo,NCKU Institite of Electro-Optical Science & Engineering,4,Typical Semiconducting Materials,T.-F. Guo,NCKU Institite of Electro-Optical Science & Engineering,5,Energy Band Diagram of a conductor, semiconductor, and insulator,T.-F. Guo,NCKU Institite of Electro-Optical Science & Engineering,6,Beginning of orgnaic semiconductor ( bonding),Side-by-Side Bonding,T.-F. Guo,NCKU Institite of Electro-Optical Science & Engineering,7,Conjugated (共軛): alternatively double-single bonds,T.-F. Guo,NCKU Institite of Electro-Optical Science & Engineering,8,Bang Gap of Polyacetylene,T.-F. Guo,NCKU Institite of Electro-Optical Science & Engineering,9,Conjugated polymer,T.-F. Guo,NCKU Institite of Electro-Optical Science & Engineering,10,Creating new materials from old materials,T.-F. Guo,NCKU Institite of Electro-Optical Science & Engineering,11,Delocalization of Charge Carriers in Polyacetylene,Localized! Charge cannot go anywhere!,Delocalized! Charge carriers can move around!,T.-F. Guo,NCKU Institite of Electro-Optical Science & Engineering,12,Delocalization and Transport of Charge Carriers,T.-F. Guo,NCKU Institite of Electro-Optical Science & Engineering,13,Conjugated Polymers: Basic Materials and Chemistry,Conduction polymers: Polyacetylene, Polyaniline, PEDOT/PSS etc. Semiconducting polymers: Polythiophenes, Oligothiophenes etc. Light-emitting/Photovoltaic Polymers: Poly-(para-phenylene-vinylene), Poly(para-phenylene), Polyfluorene etc.,T.-F. Guo,NCKU Institite of Electro-Optical Science & Engineering,14,Scientific Interest in Organic Materials,1950s steady work on crystalline organics starts 1970s organic photoconductors (Xerography) 1980s organic non-linear optical materials 1987 Kodak first published the efficient organic light-emitting devices (OLED) 1990 Cambridge groups publish the first polymer light-emitting diodes (PLED) Since then, the field has dramatically expanded both commercially and scientifically, including OLED, PLED, transistors, potovoltaic, solar cells,T.-F. Guo,NCKU Institite of Electro-Optical Science & Engineering,15,What are the OLEDs?,Invented by Dr. Ching W Tang （鄧青雲博士）(kodak) 1987年 OLED 全名叫做有機發光二極體 (Organic Light-Emitting Diode) 部分國外又稱 OEL為有機電激光顯示 (Organic Electroluminescence Display),T.-F. Guo,NCKU Institite of Electro-Optical Science & Engineering,16,OLED Basic Device Configuration,Double layers structure 電洞傳輸層-Hole Transport (injection) Layer (HTL) 電子傳輸層 Electron Transport Layer (ETL) 發光層- Emitting Layer (EML),T.-F. Guo,NCKU Institite of Electro-Optical Science & Engineering,17,First OLED Invented by Dr. Ching W Tang (kodak) 1987,T.-F. Guo,NCKU Institite of Electro-Optical Science & Engineering,18,Absorption, Fluorescence & Phosphorescence Process,T.-F. Guo,NCKU Institite of Electro-Optical Science & Engineering,19,Singlet excitons,Triplet excitons,h1,h2,fluorescence,non-radiation,heat,e-/h+,dissociation,recombination,Intersystem crossing,T-T annihilation,phosphorescence,dissociation,carrier separation,carrier injection,Photophysics process,ground state,T.-F. Guo,NCKU Institite of Electro-Optical Science & Engineering,20,Operation of OLEDs,T.-F. Guo,NCKU Institite of Electro-Optical Science & Engineering,21,Electroluminescence of O/PLED,T.-F. Guo,NCKU Institite of Electro-Optical Science & Engineering,22,Mechanism of Electroluminescence,T.-F. Guo,NCKU Institite of Electro-Optical Science & Engineering,23,Fluorescence and Phosphorescence,Decay from singlet allowed by symmetry: fast and often efficient.,Decay from triplet disallowed by symmetry: slow and usually inefficient.,25%,75%,Singlet exciton,Triplet exciton,T.-F. Guo,NCKU Institite of Electro-Optical Science & Engineering,24,Device preparation,ITO/Glass substrate,Organic materials,Vacuum10-5 torr,Lecture note of Prof. Chou, NTU Phys.,T.-F. Guo,NCKU Institite of Electro-Optical Science & Engineering,25,What are PLEDs?,Invented by Richard. H. Friend (University of Cambridge, Cavendish Laboratory) 1990年 PLED 全名叫做高分子發光二極體 (Polymer Light-Emitting Diode) Usually for single layer device configuration,T.-F. Guo,NCKU Institite of Electro-Optical Science & Engineering,26,First PLED Invented by Richard. H. Friend (Cambridge University, Cavendish Laboratory)1990,T.-F. Guo,NCKU Institite of Electro-Optical Science & Engineering,27,Synthetic Route to PPV,J. H. Burroughes, D. D. C. Bradley, A. R. Brown, R. N. Marks, K. Mackay, R. H. Friend, P. L. Burns, and A. B. Holmes, Nature, 347, 539 (1990).,T.-F. Guo,NCKU Institite of Electro-Optical Science & Engineering,28,Schematic Energy Level Diagram,T.-F. Guo,NCKU Institite of Electro-Optical Science & Engineering,29,Processing for the fabrication of a typical PLED,Spin coating PEDOT layer & baking,Spin coating MEH-PPV layer & baking,PEDOT:PSS,T.-F. Guo,NCKU Institite of Electro-Optical Science & Engineering,30,PLED Devices at NCKU,T.-F. Guo,NCKU Institite of Electro-Optical Science & Engineering,31,Why they are so important?,http:/www.nobel.se/chemistry/laureates/2000/illpres/7.html,Self-luminescent No viewing angle limitation Thin, Light weight Low operation voltage Flexible substrate application,T.-F. Guo,NCKU Institite of Electro-Optical Science & Engineering,32,20 inches, amorphous Si, active matrix, full color OLED display WXGA (1280 x 768 pixels), 25 W, 300 cd/m2, CMO 03/12/2003,Recent progress of EL Panels,Kodak digital camera, available on April 2003,Ink-jet printed EL display, Toshiba and Epson 2002,T.-F. Guo,NCKU Institite of Electro-Optical Science & Engineering,33,Reasons for organic solar cells,Organic solar cells: moderate efficiencies and very low cost,S.E. Shaheen, D.S. Ginley, G.E. Jabbour, Mrs. Bull., 30, pp.10-18(2005).,T.-F. Guo,NCKU Institite of Electro-Optical Science & Engineering,34,A Flexible, printed plastic solar cell with high efficiency made by SIMENS AG,Flexible Donor-acceptor type solar cells,T.-F. Guo,NCKU Institite o