• Journal of the Korean Ceramic Society
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• v.54 no.2
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• pp.137-140
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• 2017

A $TiO_2$ nanofilm was deposited on ${\alpha}-Fe_2O_3$ nanopowders using the atomic layer deposition method. The $TiO_2$ film was prepared at $300^{\circ}C$ using $Ti(N(CH_3)_2)_4$ and $H_2O$ as the precursor and reactant gas, respectively. The thickness and composition of the $TiO_2$ surface were characterized by TEM and EDS measurements. The TEM results showed that the growth rate of the film was about $0.12{\AA}/cycle$. The EDS and SAED analyses showed the presence of titanium oxide on the surface of the ${\alpha}-Fe_2O_3$ nanopowders, confirming the deposition of the $TiO_2$ nanofilm. The Zeta potential and sedimentation test results showed that the dispersibility of the coated nanopowders was higher than that of the uncoated nanopowders. This is attributed to the electrostatic repulsion between the $TiO_2$-coated layers on the surface of the ${\alpha}-Fe_2O_3$ nanopowders. The results revealed that the $TiO_2$-coated layers modified the surface characteristics of the ${\alpha}-Fe_2O_3$ nanopowders and improved their dispersibility.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2000.11a
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• pp.120-123
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• 2000

This paper reports a newly developed sol-gel process to synthesize dense YBCO thick films with BaTiO$_3$additives using electrophoretic deposition and metal alkoxide sol/particle suspension, which we successfully produce dense $YBCO+BaTiO_3$ ceramics at a rather low temperature, compared with the sintering temperature used in conventional methods. The thick films of HTS were prepared by electrophoretic deposition, using pre-sintered powder with barium titanate addition in the form of $BaTi(OR)_6$ solution in suspension for electrophoresis. The conditions for applied voltage and deposition times for electrophoretic deposition of HTS thick films were studied in detail.

• Proceedings of the KSME Conference
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• 2004.04a
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• pp.956-960
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• 2004

Effects of ion implantation and deposition on the tribological properties of DLC film as a function of implanted energies and process times were investigated. TiC ions were implanted and deposited on the Si-wafer substrates followed by DLC coating using ion beam deposition method. In order to study tribological properties such as friction coefficient and behavior of DLC film on the modified surface as a function of implanted energies and process times, we used a ball-on-disc type apparatus in the atmospheric environment. From results of wear test, as the implanted energy was increased, the friction coefficient was more stable below 0.1.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2000.11a
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• pp.120-123
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• 2000

This paper reports a newly developed sol-gel process to synthesize dense YBCO thick films with $BaTiO_3$ additives using electrophoretic deposition and metal alkoxide sol/particle suspension, which we successfully produce dense $YBCO+BaTiO_3$ ceramics at a rather low temperature, compared with the sintering temperature used in conventional methods. The thick films of HTS were prepared by electrophoretic deposition, using pre-sintered powder with barium titanate addition in the form of $BaTi(OR)_6$ solution in suspension for electrophoresis. The conditions for applied voltage and deposition times for electrophoretic deposition of HTS thick films were studied in detail.

• Journal of the Korean Electrochemical Society
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• v.14 no.2
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• pp.104-109
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• 2011

We fabricated CdSe-sensitized photoelectrochemical solar cell by depositing CdSe nanoparticles on nanoporous $TiO_2$ (np-$TiO_2$) via spray pyrolysis deposition method. By adjusting the amount of CdSe-sensitizer deposited on np-$TiO_2$, we can fabricate an efficient CdSe-sensitized solar cell (${\eta}$ = 3.0% under 1 sun irradiation) in polysulfide liquid electrolyte.

• Journal of the Korean Vacuum Society
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• v.7 no.s1
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• pp.100-105
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• 1998

This paper describes the preparation of Pt-and $TiO_2$-doped $Nb_2O_5$ thin film by Ion-Beam-Enhanced Deposition. Platinum and titanium doping, and Nb2O5 deposition were carried out in situ. The dependence of oxygen sensing properties on the amounts of Pt and Ti dopant in the $Nb_2O_5$ film was investigated. There were the highist sensitivity, the lowest temperature coefficient and the shortest responce time at doping of 5 mol% $TiO_2$ and 0.3 mol%Pt

• 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.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1989.06a
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• pp.83-86
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• 1989

Lead titanate thin films with a perovskite structure were successfully structure were successfully fabricated on titanium substrate by Chemical Vapour Deposition(CVD). Analyses of Auger Electron Spectroscopy(AES) and X-ray Photoelectron Spectroscopy (XPS) have been performed in order to find a chemical composition of lead titanate films. The analysis of chemical composition by AES and XPS was investigated for variations of deposition temperature and Ti(C$_2$H$_{5}$O)$_4$ fractions. The chemical composition of PbTiO$_3$by XPS analysis was almost constant regardless of deposition parameters and the comparison of chemical composition by AES and XPS was performed.d.

• Journal of the Korean Institute of Telematics and Electronics A
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• v.29A no.8
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• pp.49-55
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• 1992

We Have investigated the properties of the titanium nitrite films widely used in VLSI devices as diffusion barrier in Al-based metallization. TiN films were formed by reactive sputtering from Ti target in Ar-N$_2$ mixtures, varying deposition parameters such as N$_2$ partial pressure, substrate temperature, power, and total pressure. All the samples received the heat treatment at 45$0^{\circ}C$ for 30 min. The resulting films are characterized by mechanical stylus($\alpha$-step), x-ray diffraction(XRD), scanning electron microscopy(SEM), and four point probe method. The Tin film properties strongly depend on the deposition condition. The stoichiometry and Ti deposition rate are critically affected by nitrogen partial pressure, and the resistivity, in particular, is dependent on both the substrate temperature and sputtering power.

• Proceedings of the IEEK Conference
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• 2003.07b
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• pp.1061-1064
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• 2003

In this paper, we deposited A1$_2$O$_3$ thin film using atomic layer deposition(ALD) method on Ti and fabricated metal-insulator-metal(MIM) capacitor. In the result of this study, the typical deposition rate was about 1.12$\AA$/cycle. About 30 nm of Ti was consumed during deposition and TiO$_{x}$ was formed at the interface of A1$_2$O$_3$ and Ti. Its surface roughness was 1.54nm. The leakage current density was 1.5 nA/$\textrm{cm}^2$. The temperature coefficient of capacitance(TCC) of MIM capacitor was 41 ppm/$^{\circ}C$ at 1MHz and 100 ppm/$^{\circ}C$ at 100 kHz.z.