학술논문
TCTA/TPBI 이중 호스트 구조를 갖는 고효율 녹색 유기 인광 발광 다이오드의 연구 / A study of high efficient Green PhOLED with TCTA/TPBI double host structure
Document Type
Dissertation/ Thesis
Author
Source
Subject
Language
Korean
Abstract
본 논문에서는 엑시톤의 적절한 속박과 엑시톤 확산에 따른 색순도의 저하를 개선하고자 TCTA/TPBI 이중 호스트 구조를 이용한 다층 발광의 녹색 유기인광 발광 다이오드를 제작하고 소자의 구조를 최적화하고 도핑 농도를 조절함으로써 이에 따른 전기·광학적 특성을 분석하였다.제작된 소자들은 Glass/ITO/DNTPD/NPB/EML/BAlq/SFC-137/LiF/Al의 기본 구조를 갖는다.또한 발광층은 [TCTA:Ir(ppy)₃/TCTA_(0.5)TPBI_(0.5):Ir(ppy)₃/TPBI:Ir(ppy)₃]의 다층 발광구조를 갖고 있으며 발광층의 총 두께를 300Å으로 고정하여 내부 두께를 변화시켜 비교하였고, 도핑 농도를 3%~9%로 변화시켜 비교하여 제작된 소자의 특성을 분석하였다.TCTA층과 TPBI층의 두께를 상호 변화시킨 실험 결과 80A 두께의 TCTA 층과 130A 두께의 TPBI 층을 갖는 소자에서 가장 우수한 전기·광학적 특성을 보였다. 또한 도핑 농도의 변화에 따른 실험 결과에서는 6%의 도핑 농도와 9%의 도핑 농도에서 유사한 효율 특성을 보였다.도핑 농도의 조절과 최적의 구조를 선택함에 따라 추가적인 정공 수송층 처리를 하여 소자의 특성을 개선하였다.구조의 최적화와 정공 수송층 처리에 따른 소자의 최대 전류효율은 63.2 cd/A 로 나타났고, 9V의 인가전압 하에서 28,760 cd/m2 의 휘도 특성을 보였다.또한 발광 스펙트럼의 EL Peak는 512nm의 중심 파장을 나타내었으며, CIE 도표 상에서 색 좌표는 (0.31, 0.62) 로 나타났으며, 이는 90% 이상의 색 순도를 나타내고 있다.
OLED-Organic Light Emitting Diodes was made of multi-layer emission by using TCTA/TPBI double host structure in order to improve the loss of the purity of color according to the appropriate restraint and diffusion of Exciton, This paper analyzed the electric & optical characteristic of by controlling the concentration of dope on these statues.The manufactured display have the basic structure of Glass/ITO/DNTPD/NPB/EML/BAlq/SFC-137/LiF/Al.Also the emitting layer have the multi-emitting layer of [TCTA:Ir(ppy)₃/TCTA_(0.5)TPBI_(0.5):Ir(ppy)₃/TPBI:Ir(ppy)₃], I fixed total thickness of emitting layers as 300Å and compared this by changing the internal thickness and compared and analyzed the characteristic of the manufactured display by changing the doping concentration from 3% to 9%.As the result on the interface change of thickness between TCTA layer and TPBI layer, TCTA layer of 80A thickness and TPBI layer of 130A thickness showed the highest electric. optical characteristic. Also in the test results according to change of doping concentration, these showed the similar characteristic of efficiency in 6% and 9% doping concentration.According to selecting the optimized structure with the control of doping concentration, the characteristics of the fabricated deviceI were improved.The maximum current efficiency for this display according to optimization of structure and handling of HTL showed 63.2 cd/A and showed the luminance of 28,760 cd/m2 at an applied voltage of 9V.Also the EL Peak of emitting spectrum showed the center wavelength and the color coordinate showed (0.31, 0.62) on the chart of CIE, these mean the purity of color is over 90%.
OLED-Organic Light Emitting Diodes was made of multi-layer emission by using TCTA/TPBI double host structure in order to improve the loss of the purity of color according to the appropriate restraint and diffusion of Exciton, This paper analyzed the electric & optical characteristic of by controlling the concentration of dope on these statues.The manufactured display have the basic structure of Glass/ITO/DNTPD/NPB/EML/BAlq/SFC-137/LiF/Al.Also the emitting layer have the multi-emitting layer of [TCTA:Ir(ppy)₃/TCTA_(0.5)TPBI_(0.5):Ir(ppy)₃/TPBI:Ir(ppy)₃], I fixed total thickness of emitting layers as 300Å and compared this by changing the internal thickness and compared and analyzed the characteristic of the manufactured display by changing the doping concentration from 3% to 9%.As the result on the interface change of thickness between TCTA layer and TPBI layer, TCTA layer of 80A thickness and TPBI layer of 130A thickness showed the highest electric. optical characteristic. Also in the test results according to change of doping concentration, these showed the similar characteristic of efficiency in 6% and 9% doping concentration.According to selecting the optimized structure with the control of doping concentration, the characteristics of the fabricated deviceI were improved.The maximum current efficiency for this display according to optimization of structure and handling of HTL showed 63.2 cd/A and showed the luminance of 28,760 cd/m2 at an applied voltage of 9V.Also the EL Peak of emitting spectrum showed the center wavelength and the color coordinate showed (0.31, 0.62) on the chart of CIE, these mean the purity of color is over 90%.