Carrier radiation distribution in organic light-emitting diodes

Abstract

This paper is based on the analysis of white organic electroluminescent device electroluminescent spectrum to explain the regular pattern of carrier radiation distribution. It has proved electron that is injected from cathode is satisfied with the regularity of radiation distribution on the organic emitting layer. This radiation distribution is related to several factors, such as electron injection capabilities, applied electrical field intensity, carrier mobility, etc. The older instruction design is ITO/2-TNATA/NPB/ADN:DCJTB:TBPe/Alq₃/cathode. Get to change electron injector capabilities through using different cathode and also find electroluminescent spectrum to produce significant changes. Simultaneously, electron radiation quantity has some limitation, and electroluminescent spectrum reflects that spectral intensity does not change anymore when the ratio of cathode dopant reaches a value, namely, the quantity of electron’s radiation distribution gets to a saturated state on the organic emitting layer. It also shows the same spectrum variational phenomenon while changing the applied electrical field intensity. To put forward of the carrier radiation distribution is good for organic light emitting diode (OLED) luminescence properties analysis and research.

Keywords

carrier radiation distribution / organic light emitting diode (OLED) / multiple dopants emission

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Acknowledgements

This research was financially supported by the National Natural Science Foundation of China (Grant No. 61076066) and the Doctor Foundation of Shaanxi University of Science and Technology (No. BJ09-07).

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2014 Higher Education Press and Springer-Verlag Berlin Heidelberg