• KIEE International Transactions on Electrophysics and Applications
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• 제3C권2호
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• pp.35-42
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• 2003

This paper proposes a relative lifetime test method of MgO thin film. The suggested test conditions are 5$0^{\circ}C$, 400Torr, 20% over-voltage and 300KHz. The relative lifetime of MgO thin film is significantly affected by the MgO preparing conditions and Xe partial pressure. As result, the lifetime of the AC plasma display panel (PDP) is increased with an MgO thickness of 2000$\AA$ to 8000$\AA$ but is saturated over 5000$\AA$ (up to 9000 $\AA$). In addition, as Xe partial pressure increases, AC PDP lifetime increases.

• 한국초전도ㆍ저온공학회논문지
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• 제9권2호
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• pp.23-26
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• 2007

The influence of water partial pressure in Metal-organic Deposition (MOD) method was investigated on the texture and the morphology of $YBa_2Cu_3O_{7-x}$ (YBCO) films grown on the buffered metal tapes. The water partial pressure was varied from 4.2% up to 10.0% with the other process variables, such as annealing temperature and oxygen partial pressure, kept constant. In this work, the fluorine-free Y & Cu precursor solution added with Sm was synthesized and coated by the continuous slot-die coating & calcination step. The next annealing step of the YBCO films was done by the reel-to-reel method with the gas flowed vertically down. From the x-ray diffraction analysis, the un-reacted phase like $BaF_2$ peak was found at the water partial pressure of 4.2%, but $BaF_2$ peak intensity is much reduced as the water partial pressure is increased. However, the higher water partial pressure of about 10% in this experiment leads to the poor crystallinity of YBCO films. The morphologies of the YBCO films were not different from each other when the water partial pressure was varied in this work. The maximum critical current density of 3.8MA/$cm^2$ was obtained at the water partial pressure of 6.2% with the annealing temperature of 780$^{\circ}C$ and oxygen partial pressure of 500ppm.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2004년도 SMICS 2004 International Symposium on Maritime and Communication Sciences
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• pp.6-8
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• 2004

The NdBaCuO superconductor samples were zone-melted in low oxygen partial pressure (1 % $O_2$＋99%Ar). The zone-melting temperature was decreased about 12$0^{\circ}C$ from 1, 06$0^{\circ}C$, the zone-melting temperature in air. Thus the loss of liquid phase (BaCu $O_2$and CuO) was reduced during the zone-melting process. The content of non-superconducting phase Nd422 in zone-melted NdBaCuO samples was clearly decreased and, therefore, the substitution of Nd for Ba was occurred. The superconductivity of zone-melted N $d_{1＋x}$B $a_{2－x}$C $u_3$ $O_{y}$prepared under low oxygen partial pressure was distinctively improved.d.d.d.

• 반도체디스플레이기술학회지
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• 제20권2호
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• pp.82-86
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• 2021

In this study, we investigated the oxygen partial pressure effect of ITO films for electrodes of oxide-based Thin-Film Transistor (TFT). Firstly, we deposited single ITO films on the glass substrate at room temperature. ITO films were prepared at the various partial pressures of oxygen gas 0-7.4% (O₂/(Ar+O₂)). As increasing oxygen on the process of film deposition, electrical properties were improved and optical transmittance increased in the visible light range (300-800 nm). For the electrode of TFT, we fabricated a TFT device (W/L=1000/200 ㎛) with ITO films as the source and drain electrode on the silicon wafer. Except for the TFT device combined with ITO film prepared at the oxygen partial pressure ratio of 7.4%, We confirmed that TFT devices with ITO films via FTS system operated as a driving device at threshold voltage (V_th) of 4V.

• E2M - 전기 전자와 첨단 소재
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• 제8권4호
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• pp.400-405
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• 1995

ZnO films have been grown easily with the conventional thermal evaporation method on SiO$\_$2/ coated Si wafers. Anhydrous zinc acetate has been used as evaporation source. Zinc-acetate was directly heated in the laboratory-made brass boat. Zinc-acetate was sublimed at the boat temperature of about 220.deg. C. The substrates were heated to 600.deg. C with home made tantalium heater. Oxygen has been flowed into the deposition chamber to change the partial pressure of oxygen. X-ray diffraction patterns showed all the films to be amorphous. The films deposited at high oxygen pressure exhibit higher resistivity than films at low pressure. Energy dispersive spectroscopy(EDS) and rutherford backscattering spectrometry(RBS) were conducted on the films to reveal the composition of the ZnO films.

• 한국진공학회지
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• 제18권2호
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• pp.141-146
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• 2009

rf magnetron sputtering 법을 이용하여 Pt/Ti/$SiO_2$/Si 기판 위에 buffer layer인 $TiO_2$ 층을 증착한 후 PLZT 강유전체 박막을 증착하였다. PLZT 박막 증착 시 가스 분압비가 박막의 특성에 미치는 영향을 알아보기 위해 Ar/$O_2$ 분압비를 각각 27/1.5 sccm, 23/5.5 sccm, 21/7.5 sccm, 19/9.5 sccm로 변화시키면서 박막을 증착하였다. 이들 박막의 구조적인 특성을 분석하기 위해 X-선 회절법을 사용하였으며 FE-SEM을 이용하여 입자상을 관찰하였다. 또한 박막의 유전특성을 분석하기 위해 Precision LC를 이용하여 이력곡선, 잔류분극, 누설전류를 측정하였다. 산소 분압이 높아질수록 박막의 결정성 및 치밀성이 저하되었으며, (110) 방향에서 (111) 방향으로 우선배향성이 변화하는 것을 확인하였다. 산소 분압비의 변화는 박막 표면 및 강유전 특성에 영향을 미치는 것으로 판단된다.

• 한국세라믹학회지
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• 제41권5호
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• pp.364-369
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• 2004

The barrier and optical properties of AlO$_{x}$ thin films on polycarbonate deposited by Reactive Ion Beam Sputtering (RIBS) were investigated at different oxygen partial pressure. We measured the deposition rate of AlO$_{x}$ thin films. As the oxygen partial pres-sure increased, the deposition rate increased then decreased. The changes of deposition rate are associated with the properties of deposited films. The properties of deposited AlO$_{x}$ thin films were studied using X-ray Photoelectron Spectroscopy (XPS), Scan-ning Electron Microscopy (SEM), and Atomic Force Microscopy (AFM). Optimum deposition parameters were found for fabricat-ing aluminum oxide thin films with high optical transparency for visible light and low Oxygen Transmission Rate (OTR). The optical transmittance of AlO$_{x}$ thin film deposited on polycarbonate (PC) showed the same value of bare PC.bare PC.

• 한국세라믹학회지
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• 제37권3호
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• pp.271-279
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• 2000

5 m/o Yb-doped SrCeO3 proton conductor was prepared by a solid state reaction method and its total electriccal conductivity measured as a function of both oxygen partial pressure and water vapor partial pressure in the temperature range of 500~100$0^{\circ}C$. From the total conductivity have been deconvoluted the partial conductivities of oxide ions, protons, and holes, respectively, on the basis of the defect model proposed. The equilibrium constant of hydrogen-dissolution reaction, proton concentration, and mobilities of oxygen vacancies and protons have subsequently been evaluated. It is verified that SrCe1-xYbxO3 is a mixed conductor of holes, protons and oxide ions and the proton conduction prevails as temperature decreases and water vapor pressure increases. The heat of water dissolution takes a representative value of $\Delta$HoH=-(140$\pm$20) kJ/mol-H2O, but tends to be less negative with increasing temperature. Migration enthalpies of proton and oxygen vacancy are extracted as 0.83$\pm$0.10 eV and 0.81$\pm$0.01 eV, respectively.

• 한국세라믹학회지
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• 제38권12호
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• pp.1093-1096
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• 2001

ZnO내 $Al_2$ $O_3$의 고용은 $Al^{3+}$ 의 ZnO 결정의 $Zn^{2+}$자리, 즉 wurtizite 구조에서 4개의 산소가 만드는 4면체 공간자리로서 치환반응으로 정의될 수 있다. 이 반응은 아연-빈자리 혹은 산소-빈자리와 연관되어 일어나므로 ZnO의 비화학량론성 및 결정결함반응들과 상관관계를 가진다. 이러한 상호연관성은 아연-빈자리 및 산소분압(P $o_2$) 의존성을 낳으며, 결과적으로 ZnO내 Al 용해도([Al/sug zn/]$_{max}$)의 산소분압 의존성을 야기한다. 본 논문은 ZnO내에 Al의 용해도는 산소분압이 증가하면 감소한다는 것을 처음으로 곗나하여 보고한다. [A $l_{zn}$ ]$_{max}$ $P_{o2}$$^{-1}$4/./.

• Nano
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• 제13권10호
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• pp.1850124.1-1850124.12
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• 2018

$TiO_2$ films were deposited from oxygen/titanium tetraisopropoxide (TTIP) plasmas at low temperature by Helicon-PECVD at floating potential ($V_f$) or substrate self-bias of -50 V. The influence of titanium precursor partial pressure on the morphology, nanostructure and optical properties was investigated. Low titanium partial pressure ([TTIP] < 0.013 Pa) was applied by controlling the TTIP flow rate which is introduced by its own vapor pressure, whereas higher titanium partial pressure was formed through increasing the flow rate by using a carrier gas (CG). Then the precursor partial pressures [TTIP+CG] = 0:027 Pa and 0.093 Pa were obtained. At $V_f$, all the films exhibit a columnar structure, but the degree of inhomogeneity is decreased with the precursor partial pressure. Phase transformation from anatase ([TTIP] < 0.013 Pa) to amorphous ([TTIP+CG] = 0:093 Pa) has been evidenced since the $O^+_2$ ion to neutral flux ratio in the plasma was decreased and more carbon contained in the film. However, in the case of -50 V, the related growth rate for different precursor partial pressures is slightly (~15%) decreased. The columnar morphology at [TTIP] < 0.013 Pa has been changed into a granular structure, but still homogeneous columns are observed for [TTIP+CG] = 0:027 Pa and 0.093 Pa. Rutile phase has been generated at [TTIP] < 0:013 Pa. Ellipsometry measurements were performed on the films deposited at -50 V; results show that the precursor addition from low to high levels leads to a decrease in refractive index.