• 제목/요약/키워드: electroluminescent

검색결과 375건 처리시간 0.023초

고분자 블렌드를 이용한 EL 소자의 임피던스 특성 (Impedance Properties of Electroluminescent Device Containing Blended Polymer Single-Layer)

  • 김주승;서부완;구할본;이경섭
    • 한국전기전자재료학회:학술대회논문집
    • /
    • 한국전기전자재료학회 2000년도 하계학술대회 논문집
    • /
    • pp.332-335
    • /
    • 2000
  • We fabricated organic electroluminescent (EL) devices with single layer of poly(3-dodeoylthiophene) (P3DoDT) hlended with different amounts of poly(N-vinylcarbazole) (PVK) as a emitting layer. The molar ratio between P3DoDT and PVK changed with 1:0, 2:1 and 1:1. To improve the external quantum efficiency of EL devices, we applied insulating layer, LiF layer, between polymer emitting layer and Al electrode. All of the devices emit orange-red light and it's can be explained that the energy transfer occurs from PVK to P3DoDT. In the voltage-current and voltage-brightness characteristics of devices applied LiF layer, current and brightness increased with increasing applied voltage. The brightness of the device have a molar ratio 1:1 with LiF layer was about 10 times larger than that of the device without PVK at 6V. Electrical impedance properties of ITO/emitting layer/LiF/Al devices were investigated. In the Cole-Cole plots of impedance data, one semicircle was observed. Therefore, the equivalent circuit for the devices can be designed as a single parallel resistor and capacitor network with series resistor.

  • PDF

피라졸 유도체를 함유한 폴리알킬플루오렌 공중합체의 향상된 EL 특성 (Highly Enhanced EL Properties of PF Copolymers with Pyrazole Derivatives)

  • 강인남;이지훈
    • 한국전기전자재료학회논문지
    • /
    • 제23권7호
    • /
    • pp.539-544
    • /
    • 2010
  • We have synthesized new blue electroluminescent polyalkylfluorene-based copolymers [poly(F-co-Py)x:y, where x:y = 99:1 or 95:5 mole ratios] containing the hole-injecting pyrazole derivative [3,3'-(4,6-bis(octyloxy)-1,3-phenylene)bis(1,5-diphenyl-4,5-dihydro-1H-pyrazole] through Ni(0) mediated polymerization, and their electroluminescent properties were investigated. Electroluminescent (EL) devices were fabricated with ITO / PEDOT:PSS (110 nm) / copolymers or PF homopolymer (80 nm) / Ca (50 nm) / Al (200 nm) configuration. Each EL device constructed from the copolymer exhibited significantly enhanced brightness and efficiency compared with a device constructed from the PF homopolymer. The EL device constructed with poly(F-co-Py)99:1 exhibited the highest luminous efficiency and brightness (0.95 cd/A and $2,907\;cd/m^2$, respectively). The achieved luminous efficiency was an excellent result, providing almost a 4-fold improvement on the efficiency obtainable with the a PF homopolymer device. This enhanced efficiency of the copolymer devices results from their improved hole injection and more efficient charge carrier balance, which arises from the HOMO level (~5.83 eV) of the poly(F-co-Py)99:1 copolymer, which is higher than that of the PF homopolyme (~5.90 eV).

열처리된 Znq2에 기초한 유기 EL소자의 발광특성 (Luminance Characteristics of Organic Electroluminescent Devices Based on Znq12 by Heating)

  • 조성렬;정은실;박수길;정평진
    • 한국재료학회지
    • /
    • 제9권6호
    • /
    • pp.564-568
    • /
    • 1999
  • The 8-hydroxyquinoline Zinc(Znq2) were prepared successfully from zinc chloride and zinc acetate as two kinds of starting material. The organic electroluminescent devices(ELDs) were fabricated by the structure of ITO/TPD/Znq2/Al with N-N'-diphenyl-N-N'-bis(3-methylphenyl)-1,1'-biphenyl-4,4'-diamine(TPD) which acts hole trasporting layer and bis(8-oxyquinolino) zinc(II)(Znq2) which acts as emission and electron transporting layer. EL efficiency of Znq2 prepared by heating was investigated. The 570nm of main emission peak which is yellowich green was investigated by photo luminesence(PL) and this results shows that electro luminescence(EL) is from Znq2. The V-J curve shows that carrier injection were investigated from 4V. Maximum luminance and luminance efficiency were 1600cd/$\m^2$, 0.9lm/W. From this results, the Znq2 can be one of the useful organic EL material.

  • PDF

절연체 종류에 따른 후막 전계 발광소자의 광학 및 전기적 특성 (Electrical and Optical Property of Powder Electroluminescent device at Dielectric variety)

  • 오주열;이종찬;박대희
    • 대한전기학회:학술대회논문집
    • /
    • 대한전기학회 1999년도 하계학술대회 논문집 D
    • /
    • pp.1800-1802
    • /
    • 1999
  • Electroluminescence is occurred when phosphor is located in electric field. In this paper, we made powder electroluminescent device (PELD) with structured ITO film/phosphor/Insulator/silver paste. The transparent electrode was ITO film and green(2704-01) and orange(2702-02) and blue-green(2703-01) were used as phosphor. The insulator was $BaTiO_3$ and $Y_2O_3$, back electrode was silver paste. To investigate electrical and optical properties of PELDs, EL spectrum, Brightness, Transferred charge density using Sawyer-Towers circuit was measured.

  • PDF