• Title/Summary/Keyword: Deposition time

Search Result 1,581, Processing Time 0.032 seconds

Alignment of Liquid Crystal on Ion-Beam Exposed ZnO Film

  • Hwang, Soo-Won;Yoon, Tae-Hoon;Kim, Jae-Chang
    • 한국정보디스플레이학회:학술대회논문집
    • /
    • 2009.10a
    • /
    • pp.648-650
    • /
    • 2009
  • We investigate nematic liquid crystal (NLC) alignment on ion-beam exposed ZnO films. ZnO is optically transparent material in the visible range. We optimized the deposition parameters such as deposition temperature and gas ratio for high transmittance and resistivity. Using ion-beam treated ZnO films, LC cells are fabricated and the conditions such as exposure energy and time for uniform alignment are found. The NLC molecules align parallel to the ion-beam exposure direction. The electro-optic and response characteristics show the possibility of application of this method in liquid crystal display.

  • PDF

Effect of annealing of Pb(La,Ti)$O_3$ thin films by Pulsed laser deposition process (펄스 레이저 증착법으로 제작된 PLT박막의 열처리 효과 연구)

  • Hur, Chang-Hoi;Shim, Kyung-Suk;Lee, Sang-Yeol
    • Proceedings of the KIEE Conference
    • /
    • 2000.07c
    • /
    • pp.1483-1484
    • /
    • 2000
  • Dielectric thin films of PLT(Pb(La.Ti)O3) for the application of highly integrated memory devices have been deposited on Pt/Ti/SiO2/Si substrates in situ by pulsed laser deposition(PLD). We have systematically investigated the variation of grain sizes depending on the condition of post-annealing and the variation of deposition rate. Both in-situ annealing and ex-situ annealing have been compared depending on the annealing time. C-V measurement, ferroelectric properties, leakage current and SEM were performed to investigate the electrical properties and the microstructural properties of Pb(La,Ti)$O_3$ films.

  • PDF

Facile Preparation of Silver Nanoparticles and Application to Silver Coating Using Latent Reductant from a Silver Carbamate Complex

  • Kim, Kyung-A;Cha, Jae-Ryung;Gong, Myoung-Seon
    • Bulletin of the Korean Chemical Society
    • /
    • v.34 no.2
    • /
    • pp.505-509
    • /
    • 2013
  • A low temperature ($65^{\circ}C$) thermal deposition process was developed for depositing a silver coating on thermally sensitive polymeric substrates. This low temperature deposition was achieved by chemical reduction of a silver alkylcarbamate complex with latent reducing agent. The effects of acetol as a latent reducing agent for the silver 2-ethylhexylcarbamate (Ag-EHCB) complex and their blend solutions were investigated in terms of reducing mechanism, and the size and shape of silver nanoparticles (Ag-NPs) as a function of reduced temperature and time, and PVP stabilizer concentration were determined. Low temperature deposition was achieved by combining chemical reduction with thermal heating at $65^{\circ}C$. A range of polymer film, sheet and molding product was coated with silver at thicknesses of 100 nm. The effect of process parameters and heat treatment on the properties of silver coatings was investigated.

The Surface Effect of Polyimide Thin Film by Vapor Deposition Polymerization Method With Plasma Treatment (진공증착중합법에 의해 제조된 폴리이미드 박막의 플라즈마 처리에 의한 표면의 변화)

  • Kim, Hyeong-Gweon;Lee, Boong-Joo;Kim, Jong-Teak;Kim, Yong-Bong;Lee, Duck-Chool
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
    • /
    • v.11 no.5
    • /
    • pp.340-346
    • /
    • 1998
  • In this study, we intended to investigate aging effect of polyimide prepared by VDPD(vapor deposition polymerized method). The prepared polymide was treated by the oxygen and argon gas plasma. And we evaluated the polyimide treated by plasma from contact angle, surface leakage current, FT-IR and SEM. We know that the structure of polyimide at surface are changed to amide structure by plasma treating. It seems that strong energy of plasma causes breaking the molecular chin of the polyimide. And surface roughness increases with plasma treating time increased and sequentially the wettability and leakage current increases.

  • PDF

The Study on Growls of diamond thin films Synthesized by Microwave Plasma Enhanced Chemical Vapor Deposition (Microwave Plasma CVD에 의한 Diamond 박막의 성장)

  • 이병수;이상희;박구범;박종관;박상현;유도현;이덕출
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
    • /
    • 1997.11a
    • /
    • pp.373-376
    • /
    • 1997
  • Diamond thin films were deposited on P-type(100) Si wafers using MPECVD. Prior to deposition, mechanical scretching was done to improve density of nucleation sites with diamond paste of 0.25${\mu}{\textrm}{m}$ size. Diamond films were deposited under the following conditions : methane concentration of 0.5~5%, oxygen concentration of 0~70%, process pressure of 70Torr, process temperature of 900~95$0^{\circ}C$, and deposition time 5hrs. The changes of the morphology and the growth rates of the deposits with the experimental conditions are expriend by Scanning Electron Microscopy. Raman Spectroscopy and X-ray Diffraction method.

  • PDF

Preparation of Titanium Microfiltration Membrane by Field-flow Fractionation Deposition

  • Wang, QiangBing;Tang, HuiPing;Zhang, QianCheng;Qiu, QunFeng;Wang, JianYong
    • Proceedings of the Korean Powder Metallurgy Institute Conference
    • /
    • 2006.09a
    • /
    • pp.312-313
    • /
    • 2006
  • The primary aim pursued by the preparation of separation membrane is the preparation of the membrane thin as well as with no defect. The field-flow fractionation deposition is a new molding technology which can overcome the traditional disadvantages such as multi-preparation to the preparation of great area of separation membrane with no defect. Therefor the mainly ingredients which influence the appearance and performance of titanium membrane layer are investigated by scanning electricity mirror (SEM) as well as porous material testing instrument: powder performance prepared and confected; selection of supporting body; sintering system such as temperature and time. It is shown that the membrane thickness can be controlled at $50{\mu}m$ or so; the filtration precision mainly rests with powder performance and selection of supporting body and little sintering system

  • PDF

Electrical Properties of the (Ba,Sr)TiO$_3$ Thin Films Prepared by PLD (PLD법으로 제작된 (Ba,Sr)TiO$_3$박막의 전기적 특성)

  • 주학림;김성구;마석범;장낙원;박정흠;박창엽
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
    • /
    • 1999.11a
    • /
    • pp.125-128
    • /
    • 1999
  • (Ba$_{0.6}$Sr$_{0.4}$)TiO$_3$(BST) thin films were fabricated with different deposition temperature by Pulsed Laser Deposition(PLD). This BST thin films showed a maximum dielectric constant value of $\varepsilon$$_{r}$=~684 and dielectric loss was ~0.01 when substrate temperature was 75$0^{\circ}C$. Charge storage density of BST thin film was 4.733 [$\mu$C/$\textrm{cm}^2$] and estimated charging time was 0.15 nsec. Leakage current density of BST thin film was below 10$^{-7}$ [A/$\textrm{cm}^2$] at 3V. 3V.V.

  • PDF

Characterization of In-Situ Film Thickness and Chamber Condition of Low-K PECVD Process with Impedance Analysis

  • Kim, Dae Kyoung;Jang, Hae-Gyu;Kim, Yong-Tae;Kim, Hoon-Bae;Chae, Hee-Yeop
    • Proceedings of the Korean Vacuum Society Conference
    • /
    • 2010.02a
    • /
    • pp.461-461
    • /
    • 2010
  • For a low dielectric constant inter-metal dielectric application, the low-k SiCOH film with a dielectric constant of 2.8-3.2 has been deposited by plasma-enhanced chemical vapor deposition with decamethylcyclopentasiloxane, cyclohexane, and helium which is carrier gas. In this work, we investigated chemical deposition rate, dielectric constant, characterization of plasma polymer films according to temperature(25C-200C) of substrate and change of component concentration. We measured impedance by using V-I prove during process. From experimental result, deposition rate decrease with increasing temperature. Through real time impedance analysis of chamber, we find corelation between film thickness and impedance by assuming equivalent circuit.

  • PDF

Determination of Germanium(IV) by Differential Pulse Anodic Stripping Voltammetry(I) (Differential Pulse Anodic Stripping Voltammetry법에 의한 게르마늄 분석에 관한 연구(제1보))

  • 문동철
    • YAKHAK HOEJI
    • /
    • v.27 no.1
    • /
    • pp.1-10
    • /
    • 1983
  • Voltammetric deposition and differential pulse anodic stripping (DPASV) of Ge(IV)at a gold electrode was investigated. Germanium (IV) exhibits two stripping peaks by DPASV in sodium borate solution, the first peak at about -1.1v. vs SCE and the second one, in the range of -0.6 to -0.2v. vs SCE. Factors affecting the sensitivity and precision included the nature of working electrode, supporting electrolytes, deposition potential, deposition time, pH, pulse height, voltage scan rate. The relative standard deviation of the measurements of the peak currents, for 100ng/ml Ge(IV), was less than ${\pm}3%$. The detection limit of Ge(IV) was 0.01ng/ml. Percent recovery in the extraction procedure of Ge(IV) from matrices by benzene in c-HCl, followed by back extraction with saturated borax solution, ranged from 96 to 104%.

  • PDF

Identification of Source Locations for Atmospheric Dry Deposition of Heavy Metals during Yellow-Sand Events in Seoul, Korea in 1998 Using Hybrid Receptor Models

  • Han, Young-Ji;Holsen, Thomas M.;Hopke, Philip K.;Cheong, Jang-Pyo;Kim, Ho;Yi, Seung-Muk
    • Proceedings of the Korean Environmental Health Society Conference
    • /
    • 2004.06a
    • /
    • pp.92-106
    • /
    • 2004
  • Elemental dry deposition fluxes were measured using dry deposition plates from March to June 1998 in Seoul, Korea. During this spring sampling period several yellow sand events characterized by long-range transport from China and Mongolia impacted the area. Understanding the impact of yellow-sand events on atmospheric dry deposition is critical to managing the heavy metal levels in the environment in Korea. In this study, the measured flux of a primarily crustal metal, Al and an anthropogenic metal, Pb was used with two hybrid receptor models, potential source contribution function (PSCF) and residence time weighted concentration (RTWC) for locating sources of heavy metals associated with atmospheric dry deposition fluxes during the yellow-sand events in Seoul, Korea. The PSCF using a criterion value of the 75th percentile of the measured dry deposition fluxes and RTWC results using the measured elemental dry deposition fluxes agreed well and consistently showed that there were large potential source areas in the Gobi Desert in China and Mongolia and industrial areas near Tianjin, Tangshan, and Shenyang in China. Major industrial areas of Shenyang, Fushun, and Anshan, the Central China loess plateau, the Gobi Desert, and the Alaskan semi-desert in China were identified to be major source areas for the measured Pb flux in Seoul, Korea. For Al, the main industrial areas of Tangshan, Tianjin and Beijing, the Gobi Desert, the Alashan semi-desert, and the Central China loess plateau were found to be the major source areas. These results indicate that both anthropogenic sources such as industrial areas and natural sources such as deserts contribute to the high dry deposition fluxes of both Pb and Al in Seoul, Korea during yellow-sand events. RTWC resolved several high potential source areas. Modeling results indicated that the long-range transport of Al and Pb from China during yellow-sand events as well as non yellow-sand spring daytimes increased atmospheric dry deposition of heavy metals in Korea.

  • PDF