• The Transactions of the Korean Institute of Electrical Engineers C
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• v.51 no.12
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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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• v.33 no.7
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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.

• Journal of the Korean Ceramic Society
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• v.26 no.5
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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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• v.29 no.2
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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.

• Journal of the Korean Ceramic Society
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• v.23 no.6
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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.

• Transactions of the Korean hydrogen and new energy society
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• v.21 no.4
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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.

• Journal of the Korean Ceramic Society
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• v.26 no.4
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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.

• Korean Journal of Crystallography
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• v.6 no.2
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• pp.111-117
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• 1995

TiO2 thin films were prepared on a (100)silicon wafer using a chemical vapor deposition(CVD) method. The deposition experiments were performed using the TTIP in the deposition temperature ransing from 200 content. The deposition rate of TiO2 was increased with the substrate temperature and the oxygen content. The thickness of the deposited thin film and the compositional analysis of this thin films with theoxygen content were measured using Ellipsometry, SEM and ESCA, respectively. The deposited thin film was composed of a bilayer, external TiO2 and internal Ti. Carbon as a residual impurity was found to remain when zero sccm O2 was purged into a reaction chamber and the composition of the deposited thin film was found to change Ti into TiO in a deeper layer. However, when 600sccm O2 was supplied to a reaction chamber, it has been found to reside less carbon content than without O2. Finally, in the condition of 1200sccm O2, no impurity level of carbon was observed and a deeper layer consisted of the Ti composite, even though the deposited surface was composed of TiO2.

• Proceedings of the Korean Vacuum Society Conference
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• 2010.02a
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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.

• Journal of the Korean Institute of Telematics and Electronics A
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• v.33A no.10
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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.