• Title/Summary/Keyword: Tellurium

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Growth of a-Se:Te thick films for Hybrid X-ray sensor technology (Hybrid 형 X선 Sensor 기술을 위한 a-Se:Te 필름의 성장)

  • Cha, Byung-Youl;Park, Ji-Koon;Choi, Jang-Yong;Kang, Sang-Sik;Kim, Jae-Hyung;Nam, Sang-Hee
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2003.05c
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    • pp.79-82
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    • 2003
  • a-Se film is known as promising medical X-ray detector material but a-Se as dopanted Tellurium is not available in X-ray detectors. a-Se thick film was grown by vacuum thermal evaporator to $3{\mu}m$ thickness. The characteristics of thick films were analyzed by XRD, U-V Meter, and SEM measurements. Te composition is 0.1, 0.3, 0.5, 0.7g. This paper is fundmental data for phosphor layer's essential parameter that selenium have absorption wavelength along to various Te concentration rate.

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Fabrication and Structural Properties of Ge-Sb-Te Thin Film by MOCVD for PRAM Application (상변화 메모리 응용을 위한 MOCVD 방법을 통한 Ge-Sb-Te 계 박막의 증착 및 구조적인 특성분석)

  • Kim, Ran-Young;Kim, Ho-Gi;Yoon, Soon-Gil
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.21 no.5
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    • pp.411-414
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    • 2008
  • The germanium films were deposited by metal organic chemical vapor deposition using $Ge(allyl)_4$ precursors on TiAlN substrates. Deposition of germanium films was only possible with a presence of $Sb(iPr)_3$, which means that $Sb(iPr)_3$ takes a catalytic role by a thermal decomposition of $Sb(iPr)_3$ for Ge film deposition. Also, as Sb bubbler temperature increases, deposition rate of the Ge films increases at a substrate temperature of $370^{\circ}C$. The GeTe thin films were fabricated by MOCVD with $Te(tBu)_2$ on Ge thin film. The GeTe films were grown by the tellurium deposition at $230-250^{\circ}C$ on Ge films deposited on TiAlN electrode in the presence of Sb at $370^{\circ}C$. The GeTe film growth on Ge films depends on the both the tellurium deposition temperature and deposition time. Also, using $Sb(iPr)_3$ precursor, GeSbTe films with hexagonal structures were fabricated on GeTe thin films. GeSbTe films were deposited in trench structure with 200 nm*120 nm small size.

Atomic Force Microscopy Study of Conducting Layered Transition Metal Ditellurides

  • Kim Sung-Jin;Park So-Jung;Oh Hoon-Jung;Jeon, Il Cheol;Song Sunae
    • Bulletin of the Korean Chemical Society
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    • v.15 no.12
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    • pp.1098-1103
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    • 1994
  • Atomic force microscopy (AFM) images of two conducting layered transition-metal ditellurides, $TaTe_2$ and $Ta_{0.5}$$V_{0.5}$$Te_2$, were examined and their surface and bulk structural features were compared. All the measured unit cell parameters from AFM image were consistent and in complete agreement with the results of the X-ray diffraction. The microscopic structures of corrugated surface tellurium sheets were strongly affected by the modification of metal double zig-zag chains underneath Te surface. Large difference in the height amplitudes of AFM images in $TaTe_2$ and $Ta_{0.5}$$V_{0.5}$$Te_2$ phases was observed and this reflects large difference in the surface electron densities of two phases. On surface, the shorter intralayer Te…Te contacts in $TaTe_2$ induce more electron transfer from Te p-block bands to Ta d-block bands, thus electron density on surface observed in $TaTe_2$ is much lower than that of $Ta_{0.5}$$V_{0.5}$$Te_2$. However, in bulk, interlayer Te…Te contacts in V substituted phase are shorter than those in $TaTe_2$ phase, thus tellurium-to-metal electron transfer occurs more easily in $Ta_{0.5}$$V_{0.5}$$Te_2$ phase.

Structural, morphological, optical, and photosensing properties of Cs2TeI6 thin film synthesized by two-step dry process

  • Hoat, Phung Dinh;Van Khoe, Vo;Bae, Sung-Hoon;Lim, Hyo-Jun;Hung, Pham Tien;Heo, Young-Woo
    • Journal of Sensor Science and Technology
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    • v.30 no.5
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    • pp.279-285
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    • 2021
  • Recently, cesium tellurium iodine (Cs2TeI6) has emerged as an inorganic halide perovskite material with potential application in optoelectronic devices due to its high absorption coefficient, suitable bandgap and because it consists of nontoxic and earth-abundant elements. However, studies on its fabrication process as well as photoresponse characteristics are limited. In this study, a simple and effective method is introduced for the synthesis of Cs2TeI6 thin films by a two-step dry process. A Cs2TeI6-based lateral photosensor was fabricated, and its photoresponse characteristics were explored under laser illuminations of four different wavelengths in the visible range: 405, 450, 520, and 655 nm. The initial photosensing results suggest potential application and can lead to more promising studies of Cs2TeI6 film in optoelectronics.

Effect of O2/Ar Gas Ratios on the Characteristics of Amorphous Tellurium Oxide Thin Films (비정질 텔루륨 산화물 박막 특성에 미치는 O2/Ar 가스비율의 영향)

  • Kong, Heon;Jung, Gun-Hong;Yeo, Jong-Bin;Lee, Hyun-Yong
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.30 no.5
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    • pp.294-300
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    • 2017
  • $TeO_x$ thin films were deposited at various $O_2$/Ar gas-flow ratios by a reactive RFmagneton sputtering technique from $TeO_2$ and Te targets. X-ray diffraction (XRD) results revealed that the $TeO_x$ thin films were amorphous. The structure and chemical composition of the $TeO_x$ thin films were investigated by fourier transform infrared spectroscopy (FT-IR) and X-ray photoelectron spectroscopy (XPS). The optical characteristics of the $TeO_x$ thin films were investigated by an Ellipsometer and a UV-VIS-NIR spectrophotometer. According to the $O_2$/Ar gas-flow ratios, the atomic composition ratio of $TeO_x$ thin films was divided into two regions(x=1-2, 2-3). Different optical characteristics were shown in each region. With an increasing $O_2$/Ar gas-flow ratio, the refractive index of the $TeO_x$ thin films decreased and the optical bandgap of the films increased.

Conversion of CdTe Nanoparticles into Nanoribbons via Self-Assembly (CdTe 나노입자의 자기조립과정을 통한 나노리본 합성)

  • Oh, Sooyeoun;Kang, Wan-Kyu;Kang, Jeong Won;Kim, Ki-Sub;Lee, Huen
    • Korean Chemical Engineering Research
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    • v.50 no.6
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    • pp.1082-1085
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    • 2012
  • CdTe nanoribbons feature their unique optical properties compared with CdTe nanoparticles. Slow oxidation of tellurium ions on CdTe nanoparticles resulted in the organization of individual nanoparticle into nanoribbons. The light-controlled self-assembly of CdTe nanoparticles led to twisted ribbons. It was found that irradiation improved the oxidation of tellurium ions. Transmission electron microscopy (TEM) were performed to characterize the synthesized nanostructures and showed nanowires were twisted after self-assembly. The photoluminescence was slightly blue-shifted from 550 to 544 nm. This synthetic procedure could potentially provide a key step toward the fabrication of nanowires.

Low-temperture Synthesis of CdTe/Te Core-shell Hetero-nanostructures by Vapor-solid Process

  • Song, Gwan-U;Kim, Tae-Hun;Bae, Ji-Hwan;Lee, Jae-Uk;Park, Min-Ho;Yang, Cheol-Ung
    • Proceedings of the Korean Vacuum Society Conference
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    • 2012.02a
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    • pp.580-580
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    • 2012
  • Heterostructures has unique and important properties, which may be helpful for finding many potential applications in the field of electronic, thermoelectric, and optoelectronic devices. We synthesized CdTe/Te core-shell heterostructures by vapor-solid process at low temperatures using a quartz tube furnace. Two step vapor-solid processes were employed. First, various tellurium structures such as nanowires, nanorods, nanoneedles, microtubes and microrods were synthesized under various deposition conditions. These tellurium nanostructures were then used as substrates in the second step to synthesize the CdTe/Te core-shell heterostructures. Using this method, various sizes, shapes and types of CdTe/Te core-shell structures were fabricated under a range of conditions. These structures were analysed by scanning electron microscopy, high resolution transmission electron microscopy, and energy dispersive x-ray spectroscopy. The vapor phase process at low temperatures appears to be an efficient method for producing a variety of Cd/Te hetero-nanostructures. In addition, the hetero-nanostructures can be tailored to the needs of specific applications by deliberately controlling the synthetic parameters.

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A study on the synthesis and characterization of CdTe nanocrystals (CdTe 나노결정의 합성과 특성분석에 관한 연구)

  • 주상민;강윤묵;김동환
    • Proceedings of the Materials Research Society of Korea Conference
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    • 2003.03a
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    • pp.111-111
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    • 2003
  • 반도체 나노결정은 양자구속효과(quantum confinement effect)에 의한 광학적인 특성을 갖기 때문에 광전자공학(optoelectronic), 광전지(photovoltaic)분야에 응용하려는 연구가 활발히 진행되고 있다. 본 연구에서는 고순도의 CdTe 나노결정을 1-thioglycerol 표면 완화제(surface stabilizer)로 사용하여 수용액 상태로 합성하였다. 모든 실험은 $N_2$ 분위기의 삼각플라스크에서 실험하였다. Cadmium 소오스로는 Cd(CIO$_4$)$_2$.6$H_2O$(Cadmium perchlorate hydrate-Aldrich)를 사용하였고 Tellurium 소오스로는 A1$_2$Te$_3$(Aluminum telluride-CERAC)와 H$_2$SO$_4$가 반응하여 H$_2$Te gas가 주입되도록 하였다. 합성된 CdTe 나노결정은 core-shell 형태로 존재하며 결정크기에 따른 특성분석을 위해서 High Resolution Transmission Electron Microscope (HRTEM), Photoluminescence spectroscopy, X-ray diffraction(XRD), UV-vis absorption spectra 분석을 하였다 또한 CdTe 나노결정을 나노와이어로 제작하여 CdTe 나노결정을 이용한 태양전지 제작에 응용하고자 한다.

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Behavior of Pt, Sb, Te during Crystallizaion of Ore Magma (I) (광화마그마내에서의 백금, 안티모니, 테루리움 거동에 관한 연구(I))

  • 김원사
    • Journal of the Mineralogical Society of Korea
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    • v.9 no.2
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    • pp.93-101
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    • 1996
  • Behavior of platinum group elements during crystallization within ore magma is of interest. In this study platinum is selected and its mineralogical and geochemical behavior in the presence of antimony and tellurium is investigated at 600$^{\circ}C$. High purity Pt, Sb, and Te are used as starting material and silica quartz tubings are as container. Rection products have been examined by use of ore microscope, X-ray diffractometer, electron microprobe analyser and micro-indentation hardness tester. stable phases at 600$^{\circ}C$ are platinum (Pt), Pt5Sb, Pt3Sb, PtSb, stumpflite (PtSb), geversite (PtSb), PtTe, Pt3Te4, Pt2Te3, moncheite (PtTe2), tellurantimony (Sb2Te3), and antimony (Sb). Geversite is the mineral showing the most significant extent of solid solution by up to 27 at% between Sb and Te elements. Isothermal section of 600$^{\circ}C$ is established in this study. It is noted that platinum cannot coexists with stumpflite or geversite under equilibrium condition, and stumpflite composition in equilibrium with geversite may be used as geothermometer.

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