• 제목/요약/키워드: Electro-optical properties

검색결과 239건 처리시간 0.026초

태양전지용 $MgF_2$ 반사방지막 특성연구 (A Study on Properties of $MgF_2$ antireflection film for solar cell)

  • 박계춘;양현훈;백수웅;나길주;소순열;이진;정해덕
    • 한국신재생에너지학회:학술대회논문집
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    • 한국신재생에너지학회 2009년도 추계학술대회 논문집
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    • pp.378-380
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    • 2009
  • $MgF_2$ is a current material for the optical applications in the UV and deep UV range. Process variables for manufacturing the $MgF_2$ thin film were established in order to clarify optimum conditions for growth of the thin film depending upon process conditions, and then by changing a number of vapor deposition conditions and substrate temperature, Annealing conditions variously, structural and Optical characteristics were measured. Thereby, optimum process variables were derived. Nevertheless, modern applications still require improvement of the optical and structural quality of the deposited layers. In the present work, the composition and microstructure of $MgF_2$ single layers grown on slide glass substrate by Electro beam Evaporator(KV-660) processes, were analyzed and compared. The surface Substrate temperature having an effect on the quality of the thin film was changed from $200[^{\circ}C]$ to $350[^{\circ}C]$ at intervals of $50[^{\circ}C]$. and annealing temperature an effect on the thin film was changed from $200[^{\circ}C]$ to $400[^{\circ}C]$ at intervals of $50[^{\circ}C]$. Physical properties of the thin film were investigated at various fabrication conditions substrate temperature, annealing and temperature, annealing time by XRD, FE-SEM.

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RF magnetron sputter에 의한 PET기판상 ITO/Al/ITO 박막의 증착 압력이 광학적 전기적 특성에 미치는 영향 (Influence of Deposition Pressure on Optical and Electrical Properties of ITO/Al/ITO Thin Films on PET by RF Magnetron Sputtering)

  • 서정은;김상호;이인선;김동원
    • 한국표면공학회지
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    • 제38권2호
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    • pp.69-72
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    • 2005
  • ITO-Al-ITO multi-layers were deposited at room temperature by RF magnetron sputtering on polyethylene terephthalate (PET). The films were deposited at various pressures of $8\times10^{-4},\;1\times10^{-3},\;4\times10^{-3},\;8\times10^{-3}\;and\;1\times10^{-2}$ Torr. A correlation between microstructure and electro-optical properties was studied. Films deposited? at low pressure have higher transmission, and lower reflectance and resistance than film deposited at high pressure. Sheet resistance, transmission, and reflectance were $141.6\Omega/\Box\;88\%\;and\;6.8\%$ resectively when the deposition pressure was $8\times10^{-4}$ torr, that was the optimum condition.

THz 전자기파를 이용한 나노시멘트 광학물성 측정 (Measurement of Optical Properties of Nano-Cement Using THz Electromagnetic Waves)

  • 김헌영;강동훈;오승재;주철민
    • 비파괴검사학회지
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    • 제36권5호
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    • pp.363-369
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    • 2016
  • 탄소나노튜브와 그래핀 등으로 대표되는 탄소 동소체기반 나노재료의 우수한 기계적 특성을 이용해 콘크리트의 압축강도를 증가시키기 위한 연구가 활발히 진행되고 있다. 일반적으로, 나노재료 적용을 통한 강도 향상을 위해서는 콘크리트 내 나노재료의 분산성이 높아야 하며, 이를 검증하기 위해 외부에서 비파괴적으로 확인할 수 있는 검사 기술이 요구된다. 본 연구에서는, 적외선의 직진성과 마이크로파의 투과성을 동시에 갖고 있는 THz 전자기파를 이용하여 MWCNT 및 GO가 포함된 두 종류의 나노시멘트 모르타르 시편을 제작하여 굴절률 및 흡수율과 같은 기초 광학물성 측정 시험을 수행하였다. 시험을 통해 일반 시멘트 모르타르에 비해 나노재료가 포함된 시편에서 굴절률은 평균 1.0~2.5%, 흡수율은 평균 -14~28% 차이로 측정됨을 확인하였다. 이를 통해, 비파괴적으로 콘크리트 내부에 포함된 나노재료의 분포도를 영상화할 수 있는 기술의 실현 가능성을 확인하였다.

Smectic Layer Reorientation Induced by AC Field

  • Song, Jun-Ho;Kim, Yong-Bae;Kumar, Satyendra;Souk, Jun-Hyung;Shin, Sung-Tae
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2002년도 International Meeting on Information Display
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    • pp.415-418
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    • 2002
  • We have studied electro-optic properties and layer deformations in the smectic phases of 4-(6ethoxy-l-trifluoromethyl-hexyloxycarbonyl)-phenyl-4-Nonyloxybiphenyl-4-carboxylat ( TFMEOHPNBC ) having fluorine attached to one of its benzene rings by electro-optical and small angle x-ray scattering techniques. 3 and 5${\mu}m$ thick test cells were prepared using beryllium plates to minimize x-ray beam absorption. Layer structure and orientation was studied while changing the amplitude and frequency of the applied electric field as a function of cell temperature. We observed that the chevron layer tilt angle is reduced and layer spacing is increased as stabilizing in antiferroelectric phase. This result is extraordinary that there is dimerization in antiferroelectric phase. We also found that there is a threshold electric field that changes the chevron structure to bookshelf structure. This threshold electric field depends on the frequency and temperature as shown in Fig.1. We will discuss the dynamics of layer orientation as determined from the x-ray, electro-optic and dielectric spectroscopy.

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저온 Roll-to-Roll 스퍼터 시스템을 이용하여 PET 기판위에 성막 시킨 ITO 박막의 전기적, 광학적, 구조적 특성 (Characteristics of amorphous indium tin oxide films on PET substrate grown by Roll-to-Roll sputtering system)

  • 조성우;배정혁;최광혁;문종민;정진아;정순욱;김한기
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2007년도 추계학술대회 논문집
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    • pp.380-381
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    • 2007
  • This paper reports on the deposition conditions and properties of ITO films used as electrode layer in a organic light emitting diodes on a PET substrate. The deposition technique employed was specially designed roll-to-roll sputtering. The oxide was deposited at room temperature in an argon and oxygen plasma on a transparent conducting ITO layer on a PET film. The influence of deposition parameters such as DC power, working pressure and oxygen partial pressure has been investigated, in order to obtain the best compromise between a high deposition rate and adequate electro-optical properties. Electrical and optical properties of ITO films were analyzed by Hall measurement examinations with van der pauw geometry at room temperature and UV/Vis spectrometer analysis, respectively. In addition, the structural properties and surface smoothness were measured by x-ray diffraction and scaning electron microscopy, respectively. From optimized ITO films grown by roll-to-roll sputter system, good electrical$(6.44{\times}10^{-4}\;{\Omega}-cm)$ and optical(above 86 % at 550 nm) properties were obtained. Also, the ITO films exhibited amorphous structure and very flat surface beacause of low deposition temperature.

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평판형 태양 전지의 광학 및 전기적 특성 최적화를 위한 에미터 전극 설계 연구 (Emitter Electrode Design to Optimize the Optical and Electrical Characteristics of Planar Solar Cells)

  • 이상복;도윤선
    • 한국광학회지
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    • 제31권1호
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    • pp.37-44
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    • 2020
  • 본 연구에서는 기본적인 평면 태양 전지 구조에 1차원 주기를 가지는 에미터 전극 배치를 통해 광학 및 전기적 효율을 최적화하는 설계방법을 제안한다. 에미터 전극의 주기가 줄어들면 애퍼처 비율이 감소해 빛 흡수율이 줄어들어 태양 전지 성능 저하에 영향을 끼친다. 본 연구에서는 시뮬레이션을 통해 가장 간단한 평판형 태양 전지 구조 내에서 에미터 전극 배열의 최적안을 제시하였다. 광학적 측면에서 에미터 전극이 없이 광흡수층 전면에서의 광흡수를 하는 레퍼런스 소자와 성능이 유사한 조건을 도출했다. 그리고 광흡수 및 전기적 효율 측면을 모두 고려하여 가장 효과적인 전극 구조를 제안하였다. 본 연구 결과는 광전 변환으로 생성된 전하를 전극으로 가장 효율적으로 전달할 수 있는 구조를 제안함으로써, 대체 에너지원에서 큰 비중을 차지하고 있는 태양 전지의 활용성을 높이는데 기여할 것이다.

유기 EL 소자의 전기-광학적 특성 (Electro-optical properties of organic EL device)

  • 김민수;박이순;박세광
    • 센서학회지
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    • 제6권4호
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    • pp.252-257
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    • 1997
  • ITO(indium-tin-oxide)/PPV(poly(p-phenylenevihylene))/음극 전극의 단층구조와 ITO /PVK(poly(N-vinylcarbazole))/PPV/음극전극의 이층구조를 가진 유기 EL(electroluminescence) 소자를 제작하였으며, 전기-광학적 특성을 측정하였다. 실험 결과, 단층구조에서는 PPV막의 열변환 온도를 $140^{\circ}C$에서 $260^{\circ}C$로 증가할수록 최대 휘도가 $118.8\;cd/m^{2}$(20V)에서 $21.14\;cd/m^{2}$(28V)으로 감소하였고, EL 스펙트럼의 최대 피크가 500nm에서 580nm로 이동하였다. 또한, 음극전극의 일함수가 낮을수록 소자의 발광휘도와 주입 전류는 증가되었다. 이층구조에서는 PVK막의 농도가 감소함에 따라 발광휘도가 $70.71\;cd/m^{2}$(32V)에서 $152.7\;cd/m^{2}$(26V)으로 증가하였다.

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스핀 코팅 공정에 따른 액정디스플레이용 폴리이미드 배향막 특성 분석 (Effect of Spin Coating Speed on Characteristics of Polyimide Alignment Layer for Liquid Crystal Display)

  • 김진아;최세훈;박홍규
    • 한국전기전자재료학회논문지
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    • 제35권1호
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    • pp.58-65
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    • 2022
  • The field of liquid crystal display (LCD) is constantly in the spotlight and the process of depositing an alignment layer in the LCD manufacturing process is very important to obtain excellent performance such as low-power driving and high-speed response to improve LCD performance. Therefore, research on liquid crystal (LC) alignment is being actively conducted. When manufacturing LCD, it is necessary to consider the effect of the alignment layer thickness as one of the factors affecting various LCD performances. In addition, previous studies confirmed the LC alignment characteristics correlate with the rotation speed in the spin coating process. Therefore, the electro-optical properties of the LCD were investigated by manufacturing a polyimide alignment layer by varying the rotation speed in the spin coating process in this study. It was confirmed that the thickness of the polyimide alignment layer was controlled according to the spin coating conditions. The average transmittances of anti-parallel LC cells at the spin coating speed of 2,500 rpm and 3,000 rpm are about 60%, which indicates that the LC cell has relatively higher performance. At the spin coating speed of 3,000 rpm, the voltage-transmittance curve of twisted nematic (TN) LC cell was below 1.5 V, which means that the TN LC cell operated at a low power. In addition, high-speed operating characteristics were confirmed with a response time of less than 30 ms. From these derived data, we confirmed that the ideal spin coating speed is 3,000 rpm. And these results provide an optimized polyimide alignment layer process when considering enhanced future LCD manufacturing.

Development of Copper Electro-Plating Technology on a Screen-Printed Conductive Pattern with Copper Paste

  • Eom, Yong-Sung;Son, Ji-Hye;Lee, Hak-Sun;Choi, Kwang-Seong;Bae, Hyun-Cheol;Choi, Jeong-Yeol;Oh, Tae-Sung;Moon, Jong-Tae
    • 마이크로전자및패키징학회지
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    • 제22권1호
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    • pp.51-54
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    • 2015
  • An electro-plating technology on a cured isotropic conductive pattern with a hybrid Cu paste composed of resin matrix, copper, and solder powders has been developed. In a conventional technology, Ag paste was used to perform a conductive pattern on a PCB or silicon substrate. From previous research, the electrical conductive mechanism and principle of the hybrid Cu paste were concisely investigated. The isotropic conductive pattern on the PCB substrate was performed using screen-printing technology. The optimum electro-plating condition was experimentally determined by processing parameters such as the metal content of the hybrid Cu paste, applied current density, and time for the electroplating in the plating bath. The surfaces and cross-sections were observed using optical and SEM photographs. In conclusion, the optimized processing conditions for Cu electro-plating technology on the conductive pattern were a current density of $40mA/cm^2$ and a plating time of 20min on the hybrid Cu paste with a metal content of 44 vol.%. More details of the mechanical properties and processing conditions will be investigated in further research.

Study of Optimized Condition for Bend State in Polymer Stabilized Pi-cell with Compensation Films

  • Jeong, Seung-Yeon;Shin, Hyun-Ho;Bos, Phil;Shin, Sung-Tae
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2003년도 International Meeting on Information Display
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    • pp.589-594
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    • 2003
  • The pi-cell [1] is known as one of the candidates for a fast response time and a good viewing angle characteristics due to a self-compensated configuration and can be a replaceable mode instead of the current TN mode and the IPS mode for moving picture in future. This paper shows the optimized condition to maintain bend state instead of splay state, which is mortal demerit for good optical properties in a pi-cell, by using the polymer stabilized method [2]. The good electro-optical characteristics are also obtained by optimizing the various factors, which are monomer concentration in a LC, UV intensity, curing time, curing voltage, and curing temperature, and by using retardation film. We use a scanning electron microscope to study the structures of the polymer stabilized polymer network in a pi-cell as a key to figure out why bend state is occurred.

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