Impedance Characteristics of Fluorescent OLED with Device Structure

Do-Hoon Kong; Sung-Hoo Ju

doi:10.3740/MRSK.2018.28.1.18

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2018 Vol.28, Issue 1 Preview Page Next Page

Impedance Characteristics of Fluorescent OLED with Device Structure 소자 구조에 따른 형광 OLED의 Impedance 특성

January 2018. pp. 18-23

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Abstract

To study the impedance characteristics of a fluorescent OLED according to the device structure, we fabricated Device 1 using ITO / NPB / Alq3 / Liq / Al, Device 2 using ITO / 2-TNATA / NPB / Alq3 / Liq / Al, and Device 3 using ITO / 2-TNATA / NPB / SH-1:BD / Alq3 / Liq / Al. The current density and luminance decreased with an increasing number of layers of the organic thin films in the order of Device 1, 2, 3, whereas the current efficiency increased. From the Cole-Cole plot at a driving voltage of 6 V, the maximum impedance values of Devices 1, 2, and 3 were respectively 51, 108, and 160 Ω just after device fabrication. An increase in the impedance maximum value is a phenomenon caused by the charge mobility and the resistance between interfaces. With the elapse of time after the device fabrication, the shape of the Cole-Cole plot changed to a form similar to 0 or a lower voltage due to the degradation of the device. As a result, we were able to see that an impedance change in an OLED reflects the characteristics of the degradation and the layer.

Keywords

OLED

fluorescence

impedance

current-voltage-luminance

elapsed time

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Information

Publisher :Materials Research Society of Korea
Publisher(Ko) :한국재료학회
Journal Title :Korean Journal of Materials Research
Journal Title(Ko) :한국재료학회지
Volume : 28
No :1
Pages :18-23
Received Date : 2017-07-24
Revised Date : 2017-10-26
Accepted Date : 2017-11-14
DOI :https://doi.org/10.3740/MRSK.2018.28.1.18

Korean Journal of Materials Research ISSN:1225-0562(Print) 2287-7258(Online) 한국재료학회지

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