• 제목/요약/키워드: Optical transmittances

검색결과 70건 처리시간 0.022초

기판 온도에 따른 ZnO:Ga 박막의 특성 (Study on the Properties of ZnO:Ga Thin Films with Substrate Temperatures)

  • 김정규;박기철
    • 한국전기전자재료학회논문지
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    • 제30권12호
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    • pp.794-799
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    • 2017
  • Ga-doped ZnO (GZO) films were deposited by an RF magnetron sputtering method on glass substrates using ZnO as a target containing 5 wt% $Ga_2O_3$ powder (for Ga doping). The structural, electrical, and optical properties of the GZO thin films were investigated as a function of the substrate temperatures. The deposition rate decreased with increasing substrate temperatures from room temperature to $350^{\circ}C$. The films showed typical orientation with the c-axis vertical to the glass substrates and the grain size increased up to a substrate temperature of $300^{\circ}C$ but decreased beyond $350^{\circ}C$. The resistivity of GZO thin films deposited at the substrate temperature of $300^{\circ}C$ was $7{\times}10^{-4}{\Omega}cm$, and it showed a dependence on the carrier concentration and mobility. The optical transmittances of the films with thickness of $3,000{\AA}$ were above 80% in the visible region, regardless of the substrate temperatures.

Highly Transparent Indium Oxide Doped ZnO Spreading Layer for GaN Based Light Emitting Diodes

  • Lim, Jae-Hong;Park, Seong-Ju
    • 한국재료학회지
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    • 제19권8호
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    • pp.443-446
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    • 2009
  • This study develops a highly transparent ohmic contact scheme using indium oxide doped ZnO (IZO) as a current spreading layer for p-GaN in order to increase the optical output power of nitride-based lightemitting diodes (LEDs). IZO based contact layers of IZO, Ni/IZO, and NiO/IZO were prepared by e-beam evaporation, followed by a post-deposition annealing. The transmittances of the IZO based contact layers were in excess of 80% throughout the visible region of the spectrum. Specific contact resistances of $3.4\times10^{-4}$, $1.2\times10^{-4}$, $9.2\times0^{-5}$, and $3.6\times10^{-5}{\Omega}{\cdot}cm^2$ for IZO, Ni/Au, Ni/IZO, and NiO/IZO, respectively were obtained. The forward voltage and the optical output power of GaN LED with a NiO/IZO ohmic contact was 0.15 V lower and was increased by 38.9%, respectively, at a forward current of 20 mA compared to that of a standard GaN LED with an Ni/Au ohmic contact due to its high transparency, low contact resistance, and uniform current spreading.

졸-겔법에 의한 강유전 BST 박막의 제조 및 특성(II) - 초음파의 효과 (Fabrication and Properties of ferroelectric BST thin films prepared by sol-gel method (II) - effect of ultrasound on properties of thin film)

  • 이진홍;박병옥;이승엽
    • 한국결정성장학회지
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    • 제11권6호
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    • pp.252-258
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    • 2001
  • ($Ba_{0.7}Sr_{0.3})TiO_3$박막을 ITO-coated glass 기판위에 spin-coating법으로 제조하였다. 제조된 용액을 초음파 bath 내에서 초음파 처리하여 균일화를 촉진시킨 후 박막을 제조하여 초음파 처리하지 않은 용액으로 제조한 박막과의 비교를 통하여 초음파 효과를 알아보았다. 용액의 초음파 처리로 박막의 결정화 온도를 다소 낮추었으며 박막의 표면이 보다 균일하고 치밀화되었고 거칠기도 8.4nm에서 5.6nm로 더 낮아졌다. 그리고 박막의 투광성 및 전기적 특성 또한 용액의 초음파 처리로 인하여 향상되었다.

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ITO Thin Film Deposition on Polycarbonate Substrate using In-Line DC Magnetron Sputtering

  • Ahn, Min-Hyung;Li, Zhao-Hui;Choi, Kyung-Min;Im, Seung-Hyeok;Jung, Kyung-Seo;Cho, Eou-Sik;Kwon, Sang-Jik
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2009년도 9th International Meeting on Information Display
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    • pp.1542-1545
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    • 2009
  • For the application of flexible substrate to future display and new transparent devices, indium tin oxide (ITO) thin film was formed on polycarbonate(PC) substrate at room temperature by in-line sputter system. During the ITO sputtering, Ar and $O_2$ reaction gas were fixed at a constant value and the process pressure was varied from 3 to 7 mtorr. From the electrical and the optical properties of sputtered ITO films, the sheet resistances of as-deposited ITO films varied with a different pressure and the optical transmittances of the ITO films at visible wavelength were maintained above 85%. The results are considered to be due to the saturation of $O_2$ atoms from reaction in ITO film.

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프로젝션 TV 적용을 위한 액정 디스플레이의 열적 안전성에 관한 연구 (Study on Thermal Stability of Liquid Crystal Display for Projection TV Application)

  • 강희진;황정연;강형구;배유한;이휘원;김영환;서대식
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2005년도 춘계학술대회 논문집 디스플레이 광소자 분야
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    • pp.177-180
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    • 2005
  • We have investigated electro-optical characteristics in three kinds of TN cells on the polyimide surface. Transmittance of no thermal stressed TN cells were better than that of thermal stressed TN cells. Also. the threshold voltage and the response time of thermal stressed TN cells were same that of no thermal stressed TN cells. There were little change of value in these TN cells. On the other hand. transmittances of TN cells on the polyimide surface decreased by increasing thermal stress time. Moreover. the residual DC of the thermal stressed TN cells on the polyimide surface showed the characteristics of thermal stressed TN cells were weakened as increasing thermal stress temperature and time. Therefore. thermal stability of TN cells were decreased gradually by giving high thermal stress for a long time.

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APPLICATION OF BENFOR'S EQUATIONS TO THE PROBLEM OF "SEEING THROUGH LAYERS"

  • Krivoshiev, Georgi -P.;Chalucova, Raina-P.;Dahm, Donald-J.
    • 한국근적외분광분석학회:학술대회논문집
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    • 한국근적외분광분석학회 2001년도 NIR-2001
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    • pp.1132-1132
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    • 2001
  • This work is a further development of the method created by G. Krivoshiev in 1996 for elimination of peel interference and prediction of fruit flesh optical density. In this investigation, as it was earlier, the objects are observed as being structured by three successive layer “AlongrightarrowOlongrightarrowB” denoting “peel-flesh-peel”. In the first version of the method the transmittances of the surface layers A and B were measured according to Kubelka-Munk theory by means of their diffuse reflectance. At that the overall transmittance T was approximated in the form of a multiplication approximation being valid for plane-parallel layers of a non-scattering material. In this work this approximation was done away with applying the theory of discontinuum, respectively Benfor's equations. As a result two mathematical models were created for non-destructive prediction of fruit flesh optical density. These models are different from the ones based solely on Kubelka-Munk theory, the destruction being marked by the terms 1n (1 - $R_{A}R_{0}$) and 1n (1 - $R_{A}R_{B}$), where: $R_{A}$ and $R_{B}$ are reflectance values for the surface layers A and B; $R_{0}$ is the average reflectance of the internal layer that could be obtained empirically by means of a preliminary measurement of sufficiently large number of physically peeled fruits of a given species and variety.

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용액증착법에 의한 광전성 CdS 박막제조 (Aqueous-deposited CdS Thin Films for Photovoltaic Application)

  • 신재혁
    • 한국결정성장학회:학술대회논문집
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    • 한국결정성장학회 1997년도 Proceedings of the 13th KACG Technical Meeting `97 Industrial Crystallization Symposium(ICS)-Doosan Resort, Chunchon, October 30-31, 1997
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    • pp.161-164
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    • 1997
  • Thin films of CdS were prepared from an aqueous solution containing Cd(Ac)$_2$, NH$_4$OH, NH$_4$Ac and (NH$_2$)$_2$CS for photovoltaic application. Growth rate of CdS films was increased with increasing temperature of reactive solution and with decreasing concentration of NH$_4$OH. Optical transmittances were more than 60%, independent with temperature and concentrations, and were changed with thickness of CdS films. Growth films mostly showed the presence of polycrystallines with mixed cubic and condition. The resistivities of CdS were decreased by doping boron and criticial amount of dopant was determined.

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Al-doped ZnO 박막의 기판 온도에 따른 전기적, 광학적 특성 (The Effect of Different Substrate Temperature on the Electrical Properties of Al-doped ZnO Thin Films)

  • 김봉석;김응권;이규일;오수영;송준태
    • 전기학회논문지
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    • 제56권10호
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    • pp.1782-1785
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    • 2007
  • In this paper, the effect of substrate temperature on structural, electrical and optical properties of aluminium-doped zinc oxide (AZO) films were investigated. AZO thin films were prepared on glass substrate by pulsed DC magnetron sputtering technique. The properties of AZO were measured by using XRD, AFM, UV spectrophotometer, and hall effect measurement system. The resistivity of AZO films was improved under the condition of high substrate temperature. The resistivity decreased from $9.95{\times}10^{-2}\;{\Omega}-cm\;to\;1.1{\times}10^{-3}\;{\Omega}-cm$ as a result of high substrate temperature and the average transmittances in visible range were above 80%.

Characteristics of Inorganic Silica-Neodymia Alloy Films as a Dielectric Layer of the Plasma Display Panel

  • Lee, Do-Kyung;Lee, Gi-Sung;Lee, Sang-Geul;Cho, Yong;Sohn, Sang-Ho
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2003년도 International Meeting on Information Display
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    • pp.810-813
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    • 2003
  • Application of inorganic silica-neodymia alloy films grown by sputtering technology to the dielectric layer of plasma display panel (PDP) is presented. The experimental results reveal that dielectric constant of the alloy films increases with neodymia concentration. Also, the alloy films act as band rejection color filter owing to sharp absorptions originating in the intratransition within the 4f shell of the $Nd^{3+}$ ion. In the optical band pass region, the transmittances of the alloy films show higher than those of commercial glass-like dielectrics. As a result, the luminance of PDP device with the alloy dielectric layer is higher than that of device with conventional dielectrics, indicating wider color gamut and higher color purity.

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진공증착법에 의한 $In_2O_3$ 투명전도막의 제작 (Fabrication of Transparent Conducting Films of $In_2O_3$ by Vacuum Deposition)

  • 이기선
    • 대한전자공학회논문지
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    • 제17권5호
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    • pp.43-47
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    • 1980
  • 전자선가열 도착법에 의해 ∼ 10-4 Torr의 산소 분권기중에서 In2O3 투명전도막을 제작하였으며, 막의 최적 훈착조건과 그의 전기적, 광학적 성질을 측정, 분석하였다. 최적 증착조건은 증착구도 3∼7 A/sec, 기판온도 300℃이상, SnO2 첨가률 2∼5 wt. % 이었으며, 이러한 조건하에서 막피 비저항은 2 × 10-4 Ω·cm 이었고, 가시광 투과률은 85∼90% 이었다.

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