• Journal of the Korean Ceramic Society
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• v.42 no.7 s.278
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• pp.455-460
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• 2005

Deposition of TiN$_{x}$ film was conducted with a DC sputtering technique. The effect of the processing parameters such as substrate temperature, deposition time, working pressure, bias power, and volumetric flowing rate ratio of Ar to N$_{2}$ gas on the resistivity of TiN$_{x}$ film was systematically investigated. Three kinds of substrates, soda-lime glass, (100) Si wafer, and 111m thermally grown (111) SiO$_{2}$ wafer were used to explore the effect of substrate. The phase of TiN$_{x}$ film was analyzed by XRD peak pattern and deposition rate was determined by measuring the thickness of TiNx film through SEM cross-sectional view. Resistance was obtained by 4 point probe method as a function of processing parameters and types of substrates. Finally, optimum condition for synthesizing TiN$_{x}$ film having lowest resistivity was discussed.

• Applied Chemistry for Engineering
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• v.17 no.5
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• pp.471-475
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• 2006

$VO_x$ thin films with the thickness of 450 nm were prepared on a $Pt/Ti/SiO_{2}/Si$ substrate at room temperature by a reactive radio frequency (rf) magnetron sputtering method. The deposition rates of $VO_x$ thin films were investigated as a function of $O_{2}$ concentration and rf power. As the $O_{2}$ concentration in a $O_{2}/Ar$ mixture increased, the deposition rate decreased. However, the deposition rate increased with increasing rf power. The deposited $VO_x$ thin films were annealed at $450^{\circ}C$ for 2, 4, and 6 h in $O_{2}$ and $N_{2}$ ambient. After annealing, the phase changes of $VO_x$ thin films were investigated using X-ray diffraction analysis. The plane and cross-sectional views of $VO_x$ thin films before and after annealing were observed by field emission scanning electron microscopy. The metal-insulator transition (MIT) properties of $VO_x$ thin films were measured using current-voltage measurement. The excellent MIT properties were observed in $VO_x$ thin films annealed in $O_{2}$ ambient.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1996.11a
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• pp.75-78
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• 1996

The deposition condition Gf TiN films as electrode was studied by sheet resistance, TiN depositon Thickness X-ray diffraction. TiN was made by reactively DC magnetron sputtering with varying $N_2$/Ar mixture gas and substrate temperature. After finding The deposition condition of TiN films, The samples with the structure of Cu/Ta$_2$O$_{5}$, TiN/Ta$_2$O$_{5}$Si, Cu/TiN/Ta$_2$O$_{5}$ Si were prepared and were measured I-V, C-V. As a results, it was found that when TiN was deposited in an $N_2$a results, it was found that when TiN was deposited in an $N_2$atmosphere its Sheet resistance is lower n than n V$_2$Ar mixtureixture

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2006.06a
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• pp.271-271
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• 2006

The structural, dielectric and piezoelectric properties of $[Bi_{1-x}(Na_{0.7-x}K_{0.2}Li_{0.1})]_{0.5}BaxTiO_3$ (BNKLBxT) ceramics were studied for the compositional range, x = 0-0.08. The samples were prepared by conventional sintering technique. The result of X-ray diffraction (XRD) suggest that $Ba^{2+}$ diffuse into the $[Bi(Na_{0.7}K_{0.2}Li_{0.1})]_{0.5}TiO_3$ (BNKLT) lattices to form a solid solution with a single phase perovskite structure. The ceramic show excellent piezoelectric and ferroelectric properties, and optimum properties measured are as follows: piezoelectric constant $d_{33}=230pC/N$, planar electromechanical coupling factor $k_p\;=\;40.3%$, remanent polarization $P_r\;=\;30\;{\mu}C/cm^2$, and coercive field $E_c\; =\;2.5\;kV/mm$, respectively.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.07a
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• pp.406-409
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• 2001

In this paper, the microstructure and the dielectric properties of the Sr$_{1-x}$ Ca$_{x}$TiO$_3$(0$\leq$$\chi$$\leq$0.2) -based grain boundary layer ceramics were investigated. The specimens were sintered from 142$0^{\circ}C$ to 152$0^{\circ}C$ for 4hr. in $N_2$ gas. The 2nd phase formed by thermal diffusing from the surface lead to a very high apparent dielectric constant, $\varepsilon$$_{r}$>50000. The structural properties of the specimens were studied by X-ray diffraction and SEM, EDX. All specimens exhibited cubic structure. Increasing content of Ca, the peak intensity were decreased.ed.d.

• Journal of the Korean Ceramic Society
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• v.47 no.3
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• pp.210-215
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• 2010

In this study, an expanded graphite-titanium oxide composite is developed from expanded graphite (EG) and titanium n-butoxide (TNB). EG is synthesized by chemical intercalation of natural graphite (NG) and rapid expansion at high temperature. TNB is used as the titanium source. The performances of the prepared EG-$TiO_2$ composite are characterized by BET surface area measurements, scan electron microscope (SEM), X-ray diffraction patterns (XRD) and energy dispersive X-ray analysis (EDX). The catalytic activities of the EG-$TiO_2$ composite are investigated by analysis of the degradation of methylene blue (MB) in aqueous solution under irradiation of UV light. Compared with the pristine $TiO_2$ and activity carbon-$TiO_2$ (AC-$TiO_2$) composite, the EG-$TiO_2$ composite shows very high efficiency against MB solution, and the EG could improve the photocatalytic effect of $TiO_2$ in the MB degradation reaction under the irradiation of UV light.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.45 no.2
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• pp.242-248
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• 1996

The properties of TiN/TiSi$_{2}$ bilayer formed by a rapid thermal annealing is investigated when thin SiO$_{2}$ film exists at the Ti-Si interface. The competitive reaction for the TiN/TiSi_2 bilayer occurs above 600 .deg. C. The thickness of the TiSi$_{2}$ layer decreases with increasing SiO$_{2}$ film thickness and also decreases with increasing anneal temperture When the competitive reaction for the TiN/TiSi$_{2}$ bilayer is occured by rapid thermal annealing, the composition of TiN layer represents TiN$_{x}$O$_{y}$ due to the SiO$_{2}$ layer at the Ti-Si interface but the structures of the TiN and TiSi$_{2}$ layers were not changed.d.d.

• Korean Journal of Materials Research
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• v.17 no.2
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• pp.68-72
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• 2007

Optimum compositions for piezoelectric properties of $(Bi_{0.5}Na_{0.5})_{(1-x)}Ba_xTiO_3$ ceramics were investigated in the range of $x=0{\sim}0.1$ covering rhombohedral to tetragonal phase regions. No impurity phases other than a perovskite phase were found and the grain size decreased with increasing x. A two-phase coexisting morphotropic phase area rather than boundary dividing rhombohedral and tetragonal phase regions appeared to exist at $x=0.05{\sim}0.08$. As for piezoelectric properties within morphotropic phase compositions, the piezoelectric constant ($d_{33}$) and the electromechanical coupling factor ($K_p$) showed peak values at x=0.065, 192 pC/N and 34%, respectively, indicating x=0.065 as an optimum composition for piezoelectric $(Bi_{0.5}Na_{0.5})_{(1-x)}Ba_xTiO_3$ ceramics.

• Electrical & Electronic Materials
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• v.8 no.2
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• pp.190-195
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• 1995

Temperature dependences of the dielectric constant K(T), remanent polarization $P_{r}$, (T), effective birefringence overbar .DELTA.n(T), transmitted light intensity and quadratic electro optic coefficient R(T) of the two-stage sintered xBa(L $a_{1}$2/N $b_{1}$2/) $O_{3}$-(1-x)Pb(Z $r_{y}$ $Ti_{1-y}$) $O_{3}$(x=0.085, 0.09, 0.40.leq.y.leq.0.70) ceramics were investigated. Increasing the PbZr $O_{3}$ contents, the crystal structure of a specimen was changed from a tetragonal phase to a rhombohedral and cubic phase, and the phase transition was showed a diffuse phase transition(DPT) characteristics. In the compositions which located on the PE-FE phase boundary, the discrepancy was observed between the Curie temperature and temperature which a microscopic polarization and effective birefringence were disappeared.red.d.

• Proceedings of the Korean Ceranic Society Conference
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• 2000.04a
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• pp.126.2-126.2
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• 2000