• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제51권12호
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• pp.567-572
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• 2002

In these days, diesel vehicle or power plant emits $NO_X\; and SO_2$ which cause air pollution like acid-rain, ozone layer destroy and optical smoke, therefore there are many kinds of methods considered for removing them such as SCR, catalyst, plasma process, and plasma-catalyst hybrid process. T$TiO_2$ is commonly used as catalyst to remove $NO_X$ gas because it have very excellent chemical characteristic as photo catalyst. In this paper, $NO_X$ sensing characteristic of $TiO_2$ thin film deposited by R.F Magnetron sputtering is investigated. A finger shaped electrode on $Al_2$O$_3$ substrate is designed and $TiO_2$ is deposited on the electrode by the magnetron sputtering deposition system. Chemical composition of the deposited $TiO_2$ thin film is $TiO_{1.9}$ by RBS analysis. When the UV is irradiated on it with flowing air, capacitance of $TiO_2$ thin film increases, however, when NO gas is put into the system with air, it immediately decreases because of photo chemical reaction. and it monotonously decreases with increasing NO concentration.

• Bulletin of the Korean Chemical Society
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• 제33권7호
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• pp.2309-2314
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• 2012

Ag deposited N-$TiO_2$ composite nanoparticles were prepared via $NH_3$ plasma treatment. X-ray diffraction, UV-vis spectroscopy, photoluminescence, and X-ray photoelectron spectroscopy were used to characterize the prepared $TiO_2$ samples. The plasma treatment did not change the phase composition and particle sizes of $TiO_2$ samples, but extended its absorption edges to the visible light region. The photocatalytic activities were tested in the degradation of an aqueous solution of a reactive dyestuff, methylene blue, under visible light. The photocatalytic activities of Ag deposited N-$TiO_2$ composite nanoparticles were much higher than Ag-$TiO_2$, N-$TiO_2$, and P25. A possible mechanism for the photocatalysis was proposed.

• 한국세라믹학회지
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• 제26권5호
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• pp.670-676
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• 1989

The PbTiO3 is well known materials having remarkable ferroelectric, piezoelectric, and pyroelectric properties. PbTiO3 thin films with a perovskite structure were successfully fabricated on titanium substrate by chemical vapor deposition. These films were characterized according to composition, crystal structure, and electrical properties. Semi-quantitative compositional analysis of the deposited films was made by Auger Electron Spectroscopy(AES). The PbTiO3 film deposited on titanium substrate at the deposition temperature 75$0^{\circ}C$, the Ti(C2H5O)4 fraction 0.15, and O2 partial pressure 0.06atm, has a columnar structure and grows with(001) preferred orientation, and has stoichiometric composition. A clear dielectric transition and offset in the dc conductivity near the transition temperature(48$0^{\circ}C$) were observed in the deposited lead titanate film.

• 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.

• 한국세라믹학회지
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• 제23권6호
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• pp.33-36
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• 1986

The $PbTiO_3$is well known materials having remarkable ferroelectric piezoelectric and pyro-electric properties. Thin films of the lead titanite has been successfully fabricated by Chemical Vapor Deposition on the borosilicate glass and titanium substrate. The $PbTiO_3$ thin film deposited on the borosilicate glass using the $PbCl_2$, $TiCl_4$ dry oxygen and wet oxygen at different temperatures (50$0^{\circ}C$-$700^{\circ}C$) grows along the (001) preferred orientation. On the other hand the $PbTiO_3$ thin film deposited on the titanium substrate using the PbO grows along the (101) preferred orientation. Growth orientation of deposited $PbTiO_3$ depends on the reaction species irrespective of substrate materials. Maximum dielectic constant and loss tangent of the $PbTiO_3$ thin film deposited on the titanium substrate are about 90 and 0.02 respectively, . Deposition rates of $PbTiO_3$ deposited on the borosilicate glass and titanium substrate are 10-15 ${\mu}{\textrm}{m}$/hr. Titanium dioxide interlayer formed be-tween $PbTiO_3$ film and titanium substrate material, It improved the adhesion of the film.

• 한국수소및신에너지학회논문집
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• 제21권4호
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• pp.301-306
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• 2010

The present work is performed to photocatalytically reduce Cr(VI) by means of metal deposited anodized $TiO_2$ tubes, which are prepared by anodization of Ti foil followed by metal deposition. Stably immobilized photo-reactive materials are favored in the field of detoxification in a conventional aqueous medium, preventing gradual loss of efficiency and process malfunction due to detachment of the materials. The prepared samples are characterized by SEM, TEM, EDAX, and photocurrent. The metal deposited-$TiO_2$ electrode shows higher efficiency for Cr(VI) reduction (ca. 20%) and higher ability for adsorption (4~5 times) than pure one.

• 한국세라믹학회지
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• 제26권4호
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• pp.539-549
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• 1989

Polycrystalline TiO2 thin films were deposited on Si and Al2O3 substrates by CVD method. Ethyl titanate, Ti(OC2H5)4, was used as a source material for Ti and O, and Ar was used for carrier gas. In the surface chemical reaction controlled deposition condition, the apparent activation energy of 6.74 Kcal/mole was obtained, and the atomic adsorption on substrate surface was proved to be governed by Rideal-Elley mechanism. In the mass transfer controlled deposition condition, the deposition rate was in a good agreement with the result which was calculated by the simple boundary layer theory. It was also observed that TiO2 thin films show different surface morphology according to the different deposition mechanism, which was fixed by deposition conditions. This phenomenon could be well explained by the surface perturbation theory.

• 한국결정학회지
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• 제6권2호
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• pp.111-117
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• 1995

화학증착법에 의해 TiO2 박막을 Si-wafer(100)위에 제조하였다. Titanium tetraisopropoxide (TTIP)를 출발물질로 하여 200-500℃의 온도범위에서 증착을 행하였다. 증착된 박막의 두께는 Ellipsometry 및 SEM을 사용하여 측정하였으며, 산소의 함량에 따른 증착층의 성분분석은 ESCA를 사용하였다. TiO2 박막의 증착속도는 산소의 함량에 따라 증가하였고, 반응가스인 산소를 공급하지 않았을 때 증착층내에 불순물로 탄소가 존재하였으며, 증착층의 성분은 내부로 갈수록 TiO2에서 Ti로 변하였다. 산소를 600scm 공급하였을 때 증착층내에 소량의 탄소가 존재하였으며, 증착층의 성분은 내부로 갈수록 TiO2에서 TiO, Ti로 됨을 알 수 있었다. 산소를 1200scm공급하였을 때 증착층내에 탄소가 존재하지 않았으며, 증착층 성분은 표면에는 TiO2를 이루나 증착층 내부로 갈수록 Ti복합화합물을 이루고 있었다.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2009년도 제38회 동계학술대회 초록집
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• pp.100-100
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• 2010

Hydrophilic $TiO_2$ films were deposited on slide glasses using titanium tetraisopropoxide (TTIP) as a precursor by metal-organic chemical vapor deposition (MOCVD). The temperature of substrate was $400^{\circ}C$ and the temperatures of precursor were kept at $75^{\circ}C$ (sample A) and $60^{\circ}C$ (sample B) during the $TiO_2$ film growth. The deposited $TiO_2$ films were characterized by contact angle measurement and uv/vis spectroscopy. The result show that sample B has very low contact angle of almost zero due to superhydrophilic $TiO_2$ surface and transmittance is $76.85%{\pm}1.47%$ at the range of 400 - 700 nm. So, this condition is very optimal for hydrophilic $TiO_2$ film deposition. However, when the temperature of precursor is lower is lower than $50^{\circ}C$ or higher than $75^{\circ}C$, $TiO_2$ could not be deposited on the substrate and cloudy $TiO_2$ film was formed due to low precursor temperature and the increase of surface roughness, respectively.

• 전자공학회논문지A
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• 제33A권10호
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• pp.98-106
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• 1996

A thin film of aluminum for ultra large scale integrated circuits metalization has been deposited on TiN and SiO$_{2}$ substrates by plasma assisted chemical vapor deposition using DMEAA (dimenthylethylamine alane) as a precursor. The effects of plasma on surface topology and growth characteristics were investigated. Thermal CVD Al could not be got continuous films on insulating subsrate such as SiO$_{2}$. However, it was found that Al films could be deposited on SiO$_{2}$ substate without any pretreatments by the hydrogen plasma for pyrolysis of DMEAA. Compared to the thermal CVD, PACVD films showed much better reflectance and resistance on TiN and SiO$_{2}$ substrate. We obtained mirror-like PACVD Al film of 90% reflectance and resistance on TiN and SiO$_{2}$ substrates. We obtained mirror-like PACVD Al film of 90% reflectance on TiN substrate. Excellent conformal step coverage was obtained on submicron contact holes ;by the PACVD blanket deposition.