skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: The Electric and Optical Properties of Doped Small Molecular Organic Light-Emitting Devices

Abstract

Organic light-emitting devices (OLEDs) constitute a new and exciting emissive display technology. In general, the basic OLED structure consists of a stack of fluorescent organic layers sandwiched between a transparent conducting-anode and metallic cathode. When an appropriate bias is applied to the device, holes are injected from the anode and electrons from the cathode; some of the recombination events between the holes and electrons result in electroluminescence (EL). Until now, most of the efforts in developing OLEDs have focused on display applications, hence on devices within the visible range. However some organic devices have been developed for ultraviolet or infrared emission. Various aspects of the device physics of doped small molecular OLEDs were described and discussed. The doping layer thickness and concentration were varied systematically to study their effects on device performances, energy transfer, and turn-off dynamics. Low-energy-gap DCM2 guest molecules, in either α-NPD or DPVBi host layers, are optically efficient fluorophores but also generate deep carrier trap-sites. Since their traps reduce the carrier mobility, the current density decreases with increased doping concentration. At the same time, due to efficient energy transfer, the quantum efficiency of the devices is improved by light doping or thin doping thickness, in comparison withmore » the undoped neat devices. However, heavy doping induces concentration quenching effects. Thus, the doping concentration and doping thickness may be optimized for best performance.« less

Authors:
 [1]
  1. Iowa State Univ., Ames, IA (United States)
Publication Date:
Research Org.:
Ames Lab., Ames, IA (United States)
Sponsoring Org.:
USDOE Office of Science (SC)
OSTI Identifier:
816444
Report Number(s):
IS-T 2031
TRN: US0305026
DOE Contract Number:  
W-7405-Eng-82
Resource Type:
Thesis/Dissertation
Resource Relation:
Other Information: TH: Thesis (Ph.D.); Submitted to the Iowa State Univ., Ames, IA (US); PBD: 5 Aug 2003
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; ANODES; CARRIER MOBILITY; CURRENT DENSITY; ELECTROLUMINESCENCE; ELECTRONS; ENERGY TRANSFER; OPTICAL PROPERTIES; PERFORMANCE; PHYSICS; QUANTUM EFFICIENCY; QUENCHING; RECOMBINATION; THICKNESS

Citation Formats

Cheon, Kwang-Ohk. The Electric and Optical Properties of Doped Small Molecular Organic Light-Emitting Devices. United States: N. p., 2003. Web. doi:10.2172/816444.
Cheon, Kwang-Ohk. The Electric and Optical Properties of Doped Small Molecular Organic Light-Emitting Devices. United States. doi:10.2172/816444.
Cheon, Kwang-Ohk. Wed . "The Electric and Optical Properties of Doped Small Molecular Organic Light-Emitting Devices". United States. doi:10.2172/816444. https://www.osti.gov/servlets/purl/816444.
@article{osti_816444,
title = {The Electric and Optical Properties of Doped Small Molecular Organic Light-Emitting Devices},
author = {Cheon, Kwang-Ohk},
abstractNote = {Organic light-emitting devices (OLEDs) constitute a new and exciting emissive display technology. In general, the basic OLED structure consists of a stack of fluorescent organic layers sandwiched between a transparent conducting-anode and metallic cathode. When an appropriate bias is applied to the device, holes are injected from the anode and electrons from the cathode; some of the recombination events between the holes and electrons result in electroluminescence (EL). Until now, most of the efforts in developing OLEDs have focused on display applications, hence on devices within the visible range. However some organic devices have been developed for ultraviolet or infrared emission. Various aspects of the device physics of doped small molecular OLEDs were described and discussed. The doping layer thickness and concentration were varied systematically to study their effects on device performances, energy transfer, and turn-off dynamics. Low-energy-gap DCM2 guest molecules, in either α-NPD or DPVBi host layers, are optically efficient fluorophores but also generate deep carrier trap-sites. Since their traps reduce the carrier mobility, the current density decreases with increased doping concentration. At the same time, due to efficient energy transfer, the quantum efficiency of the devices is improved by light doping or thin doping thickness, in comparison with the undoped neat devices. However, heavy doping induces concentration quenching effects. Thus, the doping concentration and doping thickness may be optimized for best performance.},
doi = {10.2172/816444},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Wed Jan 01 00:00:00 EST 2003},
month = {Wed Jan 01 00:00:00 EST 2003}
}

Thesis/Dissertation:
Other availability
Please see Document Availability for additional information on obtaining the full-text document. Library patrons may search WorldCat to identify libraries that hold this thesis or dissertation.

Save / Share: