首页 | 本学科首页   官方微博 | 高级检索  
     


Detailed evaluation of in-operando potentials in OLED devices: A combined experimental and drift-diffusion study
Affiliation:1. InnovationLab GmbH, Speyerer Straße 4, 69115, Heidelberg, Germany;2. Technische Universität Darmstadt, Materials Science Department, Surface Science Division, Jovanka-Bontschits-Straße 2, 64287, Darmstadt, Germany;3. Merck KGaA, Frankfurter Straße 250, 64293, Darmstadt, Germany;1. XLIM, UMR-CNRS 7252, University of Limoges, 123 Avenue Albert Thomas, 87060 Limoges Cedex, France;2. Laboratoire de Chimie des Substances Naturelles, Université de Limoges, 123 Av. Albert Thomas, 87060 Limoges, France;3. CEISAM UMR CNRS 6230, Université de Nantes, UFR sciences et techniques 2 rue de la Houssinière BP 92208, 44322 Nantes Cedex 03, France;1. Institute of Organoelement Compounds of the Russian Academy of Sciences, Vavilova St., 28, Moscow 119991, Russian Federation;2. Nanotechnology and Advanced Materials Laboratory, Department of Chemical Engineering, University of Patras, Patras 26500 GR, Greece;3. Molecular Engineering Laboratory, Department of Physics, University of Patras, Patras 26500 GR, Greece;4. Department of Physics, The LNM Institute of Information Technology, Jamdoli, Jaipur 302031, Rajasthan, India;1. Key Laboratory of Interface Science and Engineering in Advanced Materials, Ministry of Education, Taiyuan University of Technology, Taiyuan 030024, PR China;2. Research Center of Advanced Materials Science and Technology, Taiyuan University of Technology, Taiyuan 030024, PR China;3. Key Laboratory of Advanced Transducers and Intelligent Control System of Ministry of Education, College of Physics and Optoelectronics, Taiyuan University of Technology, Taiyuan 030024, PR China;4. State Key Laboratory of Luminescence and Applications, Changchun Institute of Optics, Fine Mechanics, and Physics, Chinese Academy of Sciences, Changchun 130033, PR China;1. Key Laboratory of Semiconductor Material Sciences, Beijing Key Laboratory of Low Dimensional Semiconductor Materials and Devices, Institute of Semiconductors, Chinese Academy of Sciences, Beijing 100083, People’s Republic of China;2. College of Materials Science and Optoelectronic Devices, University of Chinese Academy of Sciences, Beijing 100049, People’s Republic of China;1. Key Laboratory of Luminescence and Optical Information, Beijing Jiaotong University, Ministry of Education, Beijing 100044, China;2. Institute of Optoelectronics Technology, Beijing Jiaotong University, Beijing 100044, China
Abstract:We report on a technique to determine in-operando transport properties of Organic Light Emitting Diodes (OLEDs). Two types of OLEDs that solely differ in the emission layer but obviously exhibit a different potential distribution are investigated in this study. If the emission layer consists of the isomer TH-A a large shift in onset voltage can be observed in case of layer thickness variation of the emission layer. In case of the isomer TH-B a thickness variation has no impact on the onset voltage. Therefore the voltage developments per layer are determined with the help of IV measurements on a set of devices with varying layer thickness. From an empirical point of view the voltage behaviour in each layer follows a simple power law. A drift-diffusion model is developed that well describes the current density dependent evolution of coefficient and exponent of the power law. From the model we are able to derive the carrier injection mechanism into the respective layer as well as the injection barrier height. Also the carrier mobility is determined. Finally we are able to show that the existence of a large injection barrier can not explain the observed onset voltage shifts in case of TH-A. Instead an electric field at or close to the interface is necessary to describe the TH-A behaviour.
Keywords:Organic Light Emitting Diodes  Drift-diffusion  Onset voltage shift  Potential distribution
本文献已被 ScienceDirect 等数据库收录!
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号