• Title/Summary/Keyword: Vacuum Evaporation

Search Result 529, Processing Time 0.025 seconds

Properties of Inclined Silicon Carbide Thin Films Deposited by Vacuum Thermal Evaporation

  • Hamadi Oday A.;Yahia Khaled Z.;Jassim Oday N.S.
    • JSTS:Journal of Semiconductor Technology and Science
    • /
    • v.5 no.3
    • /
    • pp.182-186
    • /
    • 2005
  • In this work, thermal evaporation system was employed to deposit thin films of SiC on glass substrates in order to determine the parameters of them. Measurements included transmission, absorption, Seebak effect, resistivity and conductivity, absorption coefficient, type of energy band-gap, extinction coefficient as functions of photon energy and the effect of increasing film thickness on transmittance. Results explained that SiC thin film is an n-type semiconductor of indirect energy band-gap of ${\sim}3eV$, cut-off wavelength of 448nm, absorption coefficient of $3.4395{\times}10^{4}cm^{-1}$ and extinction coefficient of 0.154. The experimental measured values are in good agreement with the typical values of SiC thin films prepared by other advanced deposition techniques.

The effects of Se evaporation temperature on CIS absorber layer fabricated by non-vacuum process (Se 증발온도가 비진공 공정으로 제조한 CIS 광흡수층에 미치는 영향)

  • Park, Myoung-Guk;Ahn, Se-Jin;Yoon, Jea-Ho;Yoon, Kyung-Hoon
    • 한국신재생에너지학회:학술대회논문집
    • /
    • 2008.05a
    • /
    • pp.441-443
    • /
    • 2008
  • A non-vacuum process for fabrication of $CuInSe_2$ (CIS) absorber layer from the corresponding Cu, In solution precursors was described. Cu, In solution precursors was prepared by a room temperature colloidal route by reacting the starting materials $Cu(NO_3)_2$, $InCl_3$ and methanol. The Cu, In solution precursors were mixed with ethylcellulose as organic binder material for the rheology of the mixture to be adjusted for the doctor blade method. After depositing the mixture of Cu, In solution with binder on Mo/glass substrate, the samples were preheated on the hot plate in air to evaporate remaining solvents and to burn the organic binder material. Subsequently, the resultant CI/Mo/glass sample was selenized in Se evaporation in order to get a solar cell applicable dense CIS absorber layer. The CIS absorber layer selenized at $530^{\circ}C$ substrate temperature for 30 min with various Se gas evaporation temperature was characterized by XRD, SEM, EDS.

  • PDF

P-type transport characteristics of copper-oxide thin films deposited by vacuum thermal evaporation (진공열증착으로 성막된 산화구리 박막의 p-형 전도특성)

  • Lee, Ho-Nyeon;Song, Byeong-Jun
    • Journal of the Korea Academia-Industrial cooperation Society
    • /
    • v.12 no.5
    • /
    • pp.2267-2271
    • /
    • 2011
  • This study was focused on getting p-type copper-oxide thin-film semiconductors suitable for p-channel thin-film transistors. Vacuum thermal evaporation and thermal annealing were used to get copper-oxide thin-film semiconductor having properties adoptable as an active layer of thin-film transistors. n-type thin films having electron carrier density of about $10^{22}\;cm^{-3}$ before thermal annealing was converted to p-type thin films having hole carrier density of about $10^{16}\;cm^{-3}$ as the thermal annealing conditions were optimized.

An Experimental Study on the Water Evaporation Conditions of the Enclosed Tank (밀폐용기내의 물의 저압 증발 최적조건에 관한 실험적 연구)

  • Kim, S.H.;Shin, Y.S.;Lee, Y.W.;Chung, H.S.;Jeong, H.M.
    • Journal of Power System Engineering
    • /
    • v.8 no.1
    • /
    • pp.41-47
    • /
    • 2004
  • Cooling towers are widely used not only for cooling products and equipment in manufacturing process but HVAC(Heating, Ventilation and Air Conditioning) system. As a cooling tower is the terminal apparatus which discharges heat from industrial process, the efficiency of heat exchange in the cooling tower greatly affects to the overall performance of a thermal system. In this paper, we constituted a new water cooling system by using a Latent heat of evaporation in an enclosed tank, and this system is consisted of an enclosed vacuum tank and water driven ejector system. Several experimental cases were carried out for improvement methods of high vacuum pressure and water cooling characteristics. The ejector performance was tested in case of water temperature variations that flows into the ejector. Based on the vacuum pressure by water driven ejector, the water cooling characteristics were investigated for the vaporized air condensing effects.

  • PDF

Electrical Properties of CNT/Al/Cu Composite Fiber Deposited by Thermal Vacuum Evaporation (열 증착법으로 제조된 CNT/Al/Cu 복합 파이버의 전기적 특성)

  • Kim, Jong-Seok;Shin, Paik-Kyun
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
    • /
    • v.34 no.2
    • /
    • pp.105-109
    • /
    • 2021
  • CNT fiber has been in the spotlight as a conductor, but the conductivity of CNT fibers do not match that of CNT. This study reveals that the conductivity of CNT fiber can be improved by depositing Al/Cu through vacuum evaporation. Cu is commonly used for deposition on CNT fibers. But low bonding strength of the interface between CNT and Cu could be a disadvantage. To overcome this, Al was deposited on the CNT fiber for forming aluminum carbide islands to increase the interfacial bonding strength. The conductivity characteristics were improved as the deposition time increased. The resistance was measured as a function of temperature, demonstrating that the temperature coefficient of resistance (TCR) is improved to be 241 ppm/℃ in comparison with that of as-received CNT fibers at -1,251 ppm/℃, when the CNT fibers are deposited with Al and Cu, respectively, for 90s and for 540s.

The Comparison of X-ray Response Characteristics of Vacuum Evaporated $Cd_{1-x}Zn_{x}Te$ Detector (진공증착된 $Cd_{1-x}Zn_{x}Te$ 검출기의 X선 반응 특성 비교)

  • Kang, S.S.;Choi, J.Y.;Lee, D.G.;Cha, B.Y.;Kim, J.H.;Nam, S.H.
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
    • /
    • 2002.05b
    • /
    • pp.39-42
    • /
    • 2002
  • There is a renewed interest in the application of photoconductors especially Cd(Zn)Te to x-ray imaging. In this paper, We investigate effects on x-ray detection characteristic of Zn dopped CdTe detector. Cd(Zn)Te film was fabricated by vacuum thermal evaporation method and then investigate physical analysis using EPMA and XRD. We investigated the leakage current and X-ray photosensitivity as applied voltage about fabricated Cd(Zn)Te film. Experimental results showed that the increase of Zn dopped concentration in $Cd_{1-x}Zn_{x}Te$ detector reduced a leakage current and improved a signal to noise ratio significantly.

  • PDF

The Comparison of X-ray Response Characteristics of Vacuum Evaporated (진공증착된 CdTe와 $Cd_{0.85}Zn_{0.15}Te$ 필름의 X선 반응특성 비교)

  • Kang, S.S.;Choi, J.Y.;Cha, B.Y.;Moon, C.W.;Kim, J.H.;Nam, S.H.
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
    • /
    • 2002.07b
    • /
    • pp.845-848
    • /
    • 2002
  • The study of photoconductor materials is demanded for development for flat-panel digital x-ray Imager. In this paper, We investigated the feasibility of application as x-ray image sensor using Cd(Zn)Te compound with high stopping power on high radiation. These Cd(Zn)Te samples were fabricated by vacuum thermal evaporation method to large area deposition and investigated I-V measurement as applied voltage. The experimental results show that the additional injection Zn in CdTe film reduced the leakage current, for the $Cd_{0.85}Zn_{0.15}Te$ detector, the net charge had the highest value as $144.58pC/cm^2$ at 30 V.

  • PDF

Fabrication of Nanowellstructured and Nanonetstructured Metal Films using Anodic Porous Alumina Film (다공성 알루미나 박막을 이용한 금속 나노우물과 나노그물 구조의 박막 제작)

  • Noh, Ji-Seok;Chin, Won-Bai
    • Journal of the Korean Vacuum Society
    • /
    • v.15 no.5
    • /
    • pp.518-526
    • /
    • 2006
  • Nanoporous alumina film was fabricated by anodization of an aluminum sheet. Highly ordered nanowellstructured and nanonets-tructured metal films were fabricated by vacuum evaporation of several metals(Al, Sn, and Co) using the anodic nanoporous alumina film as a template. In this experiment, an anodic porous alumina film with the cell size of 100 nm and the pore diameter of 60 nm was used. The resistance heating method was adopted for evaporating a desired metal, and vapor deposition was carried out under the base pressure of torr. It was founded that whether the structure fabricated by vacuum evaporation is nanowell or nanonet is dependent on the amount of deposited material. When an anodic porous alumina film with the cell size of 100 nm and the pore diameter of 60 nm was used, a nanowell-structured film was fabricated when a sufficient amount of metal was suppled to cover the surface pores. On the other hand, nanonet-structured film was fabricated bellow a half the amount of metal required for nanowell-structured film.

A Study on a Drying Machine with Microwave at Vacuum Condition for Discarded Citrus Scrapes (감귤박 건조용 진공고주파 건조기개발에 관한 연구)

  • Ko, Gwang-Soo;Park, Youn Cheol;Yoon, Hyung-Kee
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
    • /
    • v.26 no.1
    • /
    • pp.21-25
    • /
    • 2014
  • A drying machine for discarded Citrus scrap was developed in this study. The Citrus produced in Jeju Province was treated as wastes (a) after making a beverage, such as drinking juice, and (b) if the size of the product did not fit with its agricultural product criteria. Various types of drying machine were developed in this study, and different kinds of technologies were combined improve the performance. To enhance the performance, the system was maintained in a vacuum state, and a high frequency micro wave was activated to the waste Citrus scrap, to heat up the moisture inside the Citrus kernels. The frequency of the micro-wave was 2.6 GHz, which is the resonant frequency of the molecules. Experiments were conducted with a vacuum of 50, 100, 150, 300, 500, and 700 mbar. The waste Citrus scrap has two types of status : (a) original scrap, and (b) mixed with blender. As results, specimen (a) shows a 0.13 g/sec evaporation rate, while specimen (b) shows a 0.19 g/sec rate, at 50 mbar of environment vacuum condition. For the drying efficiency, specimens (a) and (b) show 0.15 g/W and 0.24 g/W, respectively.

Comparison of characteristics of MgO films deposited by vacuum arc method with other methods. (진공아크 증착법과 다른 공정에 의해 증착된 MgO 박막 특성 비교)

  • 이은성;김종국;이성훈;이건환
    • Journal of the Korean Vacuum Society
    • /
    • v.12 no.2
    • /
    • pp.112-117
    • /
    • 2003
  • MgO films is widely used in plasma display panel (PDP) technology. In this work, structural and optical properties of the MgO films deposited by e-beam evaporation, reactive magnetron sputtering, which are commercially used, and arc deposition were compared. MgO thin films were deposited on glass substrates by vacuum arc deposition equipment using a magnesium metal target at various oxygen gas flows. In order to investigate the packing density by ellipsometer, to measure reasonable erosion-rates of the MgO protective layers, we introduced an acceleration test method, namely, Ar+ ion beam induced erosion test. Also, XPS and UV test were adopted to examine the effect of the moisture on the optical transmittance of the MgO protective layers, which showed that these of MgO films by arc deposition method sustained more 90% and were insensitive to effect of the moisture. XRD and AFM have been also used to study behaviors of the structure and surface morphology.