• 한국재료학회지
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• 제18권3호
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• pp.123-127
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• 2008

The production of tin oxide ($SnO_2$) microrods on iridium (Ir)-coated substrates was achieved through the thermal evaporation of Sn powders in which a sufficiently high $O_2$ partial pressure was employed. Scanning electron microscopy revealed that the product consisted of microrods with diameters that ranged from 0.9 to $40\;{\mu}m$. X-ray diffraction, high-resolution transmission electron microscopy, and selected area electron diffraction indicated that the microrods were $SnO_2$ with a rutile structure. As the microrod tips were free of metal particles, it was determined that the growth of $SnO_2$ microrods via the present route was dominated by a vapor-solid mechanism. The thickening of rod-like structures was related to the utilization of sufficiently high $O_2$ partial pressure during the synthesis process, whereas low $O_2$ partial pressure facilitated the production of thin rods.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 추계학술대회 논문집 Vol.14 No.1
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• pp.85-88
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• 2001

The NdBaCuO superconductor samples were Zone-melted in low oxygen partial pressure (1% $O_{2}+ 99% Ar$ ). The Zone-melting temperature was decreased about $120^{\circ}C$ from $1060^{\circ}C$ the zone-melting temperature in air. Thus the loss of liquid phase ($BaCuO_{2}$ and CuO) was reduced during the zone-melting process. The content of non-superconducting phase Nd422 in zone-melted NdBaCuO samples was clearly decreased, so was the substitution of Nd for Ba. The superconductivity of zone-melted $Nd_{1+x}Ba_{2-x}Cu_{3}O_{y}$ prepared under low oxygen partial pressure was distinctively improved.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 추계학술대회 논문집
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• pp.85-88
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• 2001

The NdBaCuO superconductor samples were Zone-melted in low oxygen partial pressure (1% O$_2$+99% Ar). The Zone-melting temperature was decreased about 120$^{\circ}C$ from 1060$^{\circ}C$ the zone-melting temperature in air. Thus the loss of liquid phase (BaCuO$_2$ and CuO) was reduced during the zone-melting process. The content of non-superconducting phase Nd422 in zone-melted NdBaCuO samples was clearly decreased, so was the substitution of Nd for Ba. The superconductivity of zone-melted Nd$\sub$1+x/Ba$\sub$2-x/Cu$_3$O$\sub$y/ prepared under low oxygen partial pressure was distinctively improved.

• 한국전기전자재료학회논문지
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• 제14권12호
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• pp.1008-1015
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• 2001

Thin films of vanadium oxide(VO$\_$x/) have been deposited by r.f. magnetron sputtering from V$_2$O$\_$5/ target in gas mixture of argon and oxygen. The oxygen/(oxygen+argon) partial pressure ratio is changed from 0% to 8%. Crystal structure, chemical composition, bonding, optical and electrical properties of films sputter-deposited under different oxygen gas pressures are characterized through XPS, AES, RBS, FTIR, optical absorption and electrical conductivity measurements. V$_2$O$\_$5/ and lower oxides co-exist in sputter-deposited films and as the oxygen partial pressure is increased the films become more stoichiometric V$_2$O$\_$5/. The increase of O/V ratio with increasing oxygen gas pressure is attributed to the partial filling of oxygen vacancies through diffusion. It is observed that the oxygen atoms located on the V-O plane of V$_2$O$\_$5/ layer participate more readily in the oxidation process. With increasing oxygen gas pressure indirect and direct optical band gaps are increased, but thermal activation energies are decreased.

• 한국표면공학회지
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• 제39권6호
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• pp.250-254
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• 2006

Effect of hydrogen partial pressure ratio on the structural and electrical properties of highly c-axis oriented ZnO films deposited by oxygen ion-assisted pulsed filtered vacuum arc at a room temperature was investigated. The hydrogen partial pressure ratio were $1.4%\sim9.8%$ at 40% oxygen pressure ratio. The conductivity of ZnO:H films was increased from 1.4% up to 4.2% due to relatively high carrier mobility caused by improvement of crystallinity While the conductivity of ZnO:H films were decreased over than 4.2% and (0002) orientation was also deteriorated. The lowest resistivity of ZnO:H films was $2.5{\times}10^{-3}\;{\Omega}{\cdot}cm$ at 4.2% of hydrogen pressure ratio. Transmittance of ZnO:H films in visible range was 85% which is lower than that of undoped ZnO films because of declined preferred orientation.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2010년도 추계학술대회 초록집
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• pp.57.1-57.1
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• 2010

ITO(Indium Tin Oxide)는 전도도와 투과도 특성이 뛰어나 디스플레이, 태양전지, LED 등 여러 산업에서 전극 물질로 널리 사용 되어져 왔다. 최근 ITO의 사용이 급격히 증가하면서 이에 대한 연구가 활발히 진행되고 있다. ITO는 막의 특성을 좋게 하기 위하여 증착 시 Ar gas와 함께 $O_2$가스를 첨가하기도 한다. 본 연구에서는 산소 분압에 따른 ITO 박막의 전기적, 광학적 특성에 대하여 연구하였다. Corning사의 eagle 2000 glass 기판위에 스퍼터링을 이용하여 ITO layer를 증측하였고, 증착시, $O_2$ partial pressure를 0 - 0.5%까지 0.1% 간격으로 가변하였다. 증착된 샘플은 Sinton사의 UV-vis 장비를 이용하여 광학적 특성을 측정하였고, Hall measurement 장비를 이용하여 전기적 특성을 측정하였다. ITO 박막은 $O_2$의 partial pressure가 증가할수록 향상된 전기적, 광학적 특성을 나타내었다.

• 한국자기학회지
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• 제7권5호
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• pp.243-248
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• 1997

Ar+ $O_{2}$ 혼합가스 중에서 반응성 스퍼터링을 통해 직접 Fe-Hf-O계 초미세결정 연자성 박막을 제조하였으며, 이때 산소분압비의 변화가 Fe-Hf-O 박막의 미세구조 및 자기적 특성에 미치는 영향을 조사하였다. 산소분압이 증가함에 따라 박막의 포화자속밀도는 점차적으로 감소하며 연자기특성이 10%까지는 향상되다가 다시 열화되는 경향을 나타내었다. 최적조건인 10%의 산소분압에서 증착한 F $e_{82}$H $f_{3.4}$ $O_{14.6}$ 초미세결정 박막은 열처리 없이 증착한 상태에서 우수한 연자기 특성을 나타내었으며, 이때의 자기적 특성은 각각 포화자속밀도 17.7 kG, 보자력 0.7 Oe 및 실효투자율 2,500(100 MHz)의 값을 나타내었다. 산소분압이 증가함에 따라 결정립 크기가 감소하며 15% 이상의 산소분압에서는 F $e_{3}$ $O_{4}$가 생성되었다. 따라서 10%에서 가장 우수한 연자기 특성을 나타내는 것은 결정립 크기와 산화물 생성에 의해 설명될 수 있다. Fe-Hf-O계 초미세결정 박막의 전기비저항은 산소분압이 증가함에 따라 증가하는 경향을 나타내었다. 우수한 연자기 특성을 나타내는 F $e_{82}$H $f_{3.4}$ $O_{14.6}$ 박막의 경우, 약 150 .mu. .ohm.cm로 산소를 첨가하지 않은 경우의 30 .mu. .ohm. cm에 비하여 약 5배 증가된 값을 나타내었다. 따라서 F $e_{82}$H $f_{3.4}$ $O_{14.6}$초미세결정 박막이 고주파에서 우수한 연자기 특성을 나타내는 원인은 주로 높은 전기비저항과 미세하게 형성된 결정립에 기이한 것으로 생각된다.

• 한국재료학회지
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• 제11권9호
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• pp.751-758
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• 2001

Anatase $TiO_2$ thin films as a photocatalyst were prepared by the D.C reactive magnetron sputtering process. The $TiO_2$ thin films were deposited on Si(100) substrates under the various conditions : oxygen partial pressure, working pressure, substrate temperature, D.C power, and deposition time. The morphology of the TiO$_2$ thin films showed an island structure. At early stages of film growth, amorphous phase formed. However, during the further growth, columnar crystalline $TiO_2$grains evolved. The crystallinity of the thin films depended on the oxygen partial pressure, the working pressure and the D.C. powers.

• 한국재료학회지
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• 제10권11호
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• pp.755-759
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• 2000

RF magnetron sputtering법으로 초미세결정 Fe-Sm-O계의 박막을 상온에서 제작하여 산소분압에 따른 포화자화, 보자력, 고주파에서의 투자율(100MHz)을 조사하였다. 최적조건인 5%의 산소분압에서 제조한 초미세결정 Fe(sub)83.4Sm(sub)3.4O(sub)13.2박막은 포화자속밀도 18kG, 보자력 0.82 Oe, 실효투자율 (0.5~100MHz) 2,600 이상의 우수한 연자성을 나타내었다. 산소분압이 증가함에 따라 $\alpha$-Fe 결정립의 크기가 감소하여 10%이상의 산소분압에서는 FeO가 생성되어 연자기적 성질이 열화되었다. Fe-Sm-O계 박막의 전기비저항은 산소분압이 증가함에 따라 증가하는 경향을 나타내었으며 우수한 연자기적 성질을 가지는 Fe(sub)83.4Sm(sub)3.4O(sub)13.2박막의 경우, 전기비저항은 130 $\mu$$\Omega$cm이었다. 따라서 미세하게 형성된 $\alpha$-Fe 결정립과 높은 전기비저항 때문에 초미세결정 Fe(sub)83.4Sm(sub)3.4O(sub)13.2박막이 고주파에서 우수한 연자기적 성질을 가지는 것으로 판단된다.

• Bulletin of the Korean Chemical Society
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• 제29권2호
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• pp.427-430
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• 2008

BaTiO3 and SrTiO3 thin films were fabricated on Pt/Ti/SiO2/Si substrate by the pulsed laser deposition process. The dependence of the deposited film quality upon the partial oxygen pressure during the deposition process was importantly examined. Regardless of the oxygen pressure, the as-deposited films were not fully crystallized. However, the film deposited at low oxygen pressure became well crystallized after the annealing process. It was concluded, therefore, that the partial oxygen pressure is reduced as low as possible during the deposition process and then anneal the as-deposited samples at ambient pressure to fabricate the well crystallized SrTiO3 and BaTiO3 films by laser ablation.