• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1999년도 추계학술대회 논문집
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• pp.602-605
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• 1999

We dried emitting layer of EL device at 30, 80, I20 and $150^{\circ}C$ for Ihr to investigate the effects to the emission characteristics of devices. PL intensity of P3HT thin film decreased with increasing the drying temperature. But, the EL intensity and stability of device with emitting layer dried at $150^{\circ}C$ were the best. We think it s because of absence of water and remaining solvent in P3HT emitting layer. So, We suggest that the drying temperature of emitting layer of EL device should be select slightly low temperature than its glass transition temperature.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1997년도 추계학술대회 논문집
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• pp.525-528
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• 1997

In this study, Eu(TTA)$_3$(phen) was synthesized and its films were prepared by vapor deposition method. Its films were characterized by UV-Vis absorption spectroscopy, Atomic Force Microscopy(AFM) and Photoluminescence(PL) measurements. Their electroluminescent(EL) characteristics were investigated by PL measurements, where a cell structure of glass substrate/ITO/Eu(TTA)$_3$(phen)/Al was employed. It was found that its films were well prepared without any decomposition and the film thickness could be controlled by adjusting the amount of Eu(TTA)$_3$(phen) in a boat. The EL spectrum of these films was almost the same as that of PL spectrum of these films.

• 마이크로전자및패키징학회지
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• 제9권1호
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• pp.9-13
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• 2002

최근, 효율적인 다층박막 구조로된 풀칼라 유기 전계발광소자 (organic electroluminescient device, OELD)의 시제품이 개발된바 있다. 본 연구에서는 ITO (indium tin oxide)/glass 투명기판위에 다층구조의 OELD 소자를 진공 열증착법으로 제작하였다. 사용된 저분자 유기화합물은 전자수송 및 주입층으로 $Alq_3$(trim-(8-hydroxyquinoline)aluminum)와 CTM (carrier transfer material) 물질을 사용하였고, 정공수송 덴 주입층으로는 TPD (triphenyl-diamine)와 CuPc (copper phthalocyanine)를 각각 증착하였다. 발광휘도는 임계전압 10 V 이상에서 급격히 증가하였으며, $A1/CTM/Alq_3$/TPD/1TO 구조로된 OELDs 소자의 경우- l7 V전압에서 430 cd/$m^2$의 휘도특성과 파장 512 nm의 녹색 발광을 나타내었다. 한편 $Li-A1/Alq_3$/TPD/CuPC/1TO 다층구조로된 소자의 발광파장은 508 nm 이며, 발광휘도는 17 V에서 650 cd/$m^2$의 값을 얻을 수 있었다. Li-Al 전극을 갖는 다층구조에서 발광휘도의 증가는 정공주입층인 CuPc의 적층으로 발광층에서 재결합 효율이 개선되었기 때문이며, 또한 Li-Al 전극의 경우 Al전극에 비해 낮은 일함수(work function)를 갖기 때문으로 판단된다.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2003년도 International Meeting on Information Display
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• pp.1047-1052
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• 2003

Controlling carrier transport in light emitting polymers is extremely important for their efficient use in organic opto-electronic devices [1]. Here we show that the interactions between single wall carbon nanotubes (SWNTs) and conjugated polymers can be used to modify the overall mobility of charge carriers within nanotube-polymer nanocomposites. By using a unique, double emitting-organic light emitting diodes (DE-OLEDs) structure. we have characterized the hole transport within electroluminescent nanocomposites (nanotubes in poly (m-phenylene vinylene-co-2,5-dioctoxy-p-phenylene) or PmPV). We have shown using this idea that single devices with color tunability can be fabricated. It is seen that SWNTs in PmPV are responsible for hole trapping, leading to shifts in the emission wavelengths. Our results could lead to improved organic optical amplifiers, semiconducting devices, and displays.

• 한국신뢰성학회지:신뢰성응용연구
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• 제9권2호
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• pp.131-148
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• 2009

An organic light emitting diode (OLED), also light emitting polymer (LEP) and organic electro luminescence (OEL), is any light emitting diode (LED) whose emissive electroluminescent layer is composed of a film of organic compounds. The layer usually contains a polymer substance that allows suitable organic compounds to be deposited. They are deposited in rows and columns onto a flat carrier by a simple "printing" process. The resulting matrix of pixels can emit light of different colors. Such systems can be used in television screens, computer displays, small, portable system screens such as cell phones and PDAs, advertising, information and indication. OLEDs can also be used in light sources for general space illumination, and large-area light-emitting elements. In this paper, we develop the general guide line of the accelerated life test for assuring B10 life of AMOLED(Active Matrix Organic Light Emitting Diode) and PMOLED(Passive Matrix Organic Light Emitting Diode) which are widely used for display monitor less than 115 mm.

• Journal of Information Display
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• 제8권2호
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• pp.20-24
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• 2007

Efficient white organic light-emitting diodes are fabricated with the blue and red electroluminescent (EL) units electrically connected in a stacked tandem structure by using a transparent doped organic p/n junction. The blue and red EL units consist of the light-emitting layer of 1,4-bis(2,2-diphenyl vinyl)benzene (DPVBi) and 4-dicyanomethylene-2-methyl-6-[2-(2,3,6,7-tetrahydro-1H,5H-benzo[i,j] quinolizin-8-yl)vinyl]-4H-pyran) (DCM2) doped tris(8-hydroxyquinoline) aluminum $(Alq_3)$, respectively. The organic p-n junction consists of ${\alpha}-NPD$ doped with $FeCl_3$ (15 % by weight ratio) and $Alq_3$ doped with Li (10 %). The EL spectra exhibit two peaks at 448 and 606 nm, resulting in white light-emission with the Commission Internationale d'Eclairage (CIE) chromaticity coordinates of (0.36, 0.24). The tandem device shows the quantum efficiency of about 2.2 % at a luminance of 100 $cd/m^2$, higher than individual blue and red EL devices.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1999년도 춘계학술대회 논문집
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• pp.601-604
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• 1999

Electroluminescence(EL) devices based on organic thin films have attracted lots of interests in large-area light-emitting display. Recently, many EL researcher have interested a new emissive organic material. In this study, light-emitting organic electroluminescent devices were fabricated using Langmuir-Blodgett(LB) technique with new emissive organic material. This new emissive organic material were synthesis by our teams and we called PECCP [poly(3,6-N-2ethylhexyl carbazoly cyanoterephthalidene)] which has strong electron donor group and electron acceptor group in main chain repeat unit. This material has good solubility in common organic solvent such as chloroform. THF, etc. and has a good stability in air. In here, the new emissive material is applied to Langmuir-Blodgett(LB) method because our new material has a good stability in air. Optimum conditions of film deposition were examined by a surface pressure-area( $\pi$ -A) isotherms with various factors. The LB film were deposited on a indium Tin Oxide(ITO) glass. We were investigated by measuring current-voltage(I-V) characteristics. Also we were measured the UV/visible absorption at about 410nm and PL spectrum at about 530nm. We are attempt to the electroluminescence device properties of the new emissive material by Langmuir-Blodgett(LB) technique.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2004년도 Asia Display / IMID 04
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• pp.348-351
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• 2004

We describe a new approach for building organic light-emitting diodes (OLEDs), which is based on physical lamination (i.e. soft contact lamination (ScL)) of thin metal electrodes supported by an elastomeric layer (polydimethylsiloxane) against an electroluminescent organic. We find that the devices fabricated have much better performance than those constructed with conventional vacuum deposition process. In addition, the ScL is intrinsically compatible with the technique of soft lithograph so that it is easy to build patterned OLEDs with feature sizes into the nanometer regime.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 하계학술대회 논문집
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• pp.648-651
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• 2001

We studied about luminance characteristics of blue organic electroluminecent device as thickness ratio. The device is fabricated TPD(N,N'-dyphenyl-N-N'-bis(3-methyphenyl) -1,1'-biphenyl-4,4'-diamine) as hole transport layer and Butyl -PBD(1,1,4,4-Tetraphenyl-1,3-butadiene) as emission layer and electron transport layer. Total thickness is 1000${\AA}$ as HTL and ETL, each devices has 500${\AA}$:500${\AA}$. 400${\AA}$:600${\AA}$ and 600${\AA}$:400${\AA}$ of TPD : Butyl-PBD. We obtained the maximum brightness about 175cd/㎡ 500${\AA}$: 500${\AA}$ thickness devices as HTL:ETL

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2005년도 International Meeting on Information Displayvol.II
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• pp.1440-1442
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• 2005

We have fabricated vertical type organic thin film transistors (OTFTs) using organic semiconductor materials such as F16CuPc, NTCDA, PTCDI C-8 and C60. The layers of OTFT were fabricated by vacuum evaporation technique and spin casting method onto the Indium Tin Oxide (ITO) coated glass. I-V characteristics and on-off ratios of the fabricated OTFTs were investigated. In addition, we have fabricated light emitting transistor using MEH-PPV and then investigated EL electroluminescent properties.