• 전자공학회논문지D
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• 제34D권6호
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• pp.50-57
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• 1997

TiO$_{2}$ tin films have been grown by MOCVD and their cahracteristics of crystallization and microstructures ahve been invetigated. Envelope mehtods are applied to the analysis of the transmission spectra to obtain the optical constants such as refractive indices and extinction coefficients for the TiO$_{2}$ thin films. The envelope methods are proved to be accurate by simulatin gthe transmission spectra. TiO$_{2}$ thin films start to crystallize at 350.deg.C and then crystallize fully into anatase phase at 400.deg.C or higher temperatures. Activation energies are obtained by plotting the deposition rate with varying the substrate temperature. It is 17.8 kcal/mol for the reaction limited regions. The refractive index and the extinction coefficient of the TiO$_{2}$ thin film at .gamma.=632.8 nm increases from 2.19 to 2.32 and decreases from 0.021 to 0.007, respectively, as the substrate temperature increases from 400 to 600.deg. C.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1992년도 춘계학술대회 논문집
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• pp.114-116
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• 1992

ITO/TiO$_2$/Se solar cell were fabricated by vacuum deposition method, the Se and TiO$_2$were deposited on the ITO/Glass. Prior to the electrical properties of film, the provide Te between the ITO and the Se film were deposited by substrate temperature 20[$^{\circ}C$] and evaporation time 15[min], next time TiO$_2$ were treated by rf-magnetron sputtering in substrate temperature 250[$^{\circ}C$]. Fabricated ITO/TiO$_2$/Se solar cell were as follows : Open Voltage V$\_$oc/=848[mV], Short Circuit Current I$\_$sc/=10.79[mA/$\textrm{cm}^2$]. Fill Factor FF=0.518, energy conversion efficiency η=4.74[%] under the illumination of AM 1.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2000년도 하계학술대회 논문집
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• pp.208-211
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• 2000

We prepared Co-Cr-Ta and Co-Cr-Ta/Ti thin film for perpendicular magnetic recording media by facing targets sputtering system (FTS system). Ti underlayer effects on crystallographic and magnetic characteristics of Co-Cr-Ta perpendicular magnetic recording media have been investigated. Crystallgraphic and magnetic characteristic of prepared thin films were evaluated by x-ray diffractometry(XRD), vibrating sample magnetometer(VSM) and kerr hysteresis loop measurement. The coercivity and anisotropy field increase by introduced Ti underlayer when substrate temperature is higher than 150$^{\circ}C$. The c-axis dispersion angle and grain size of Co-Cr-Ta/Ti thin film is decrease than Co-Cr-Ta when substrate temperature is higher than 100$^{\circ}C$. Consequently, the use of a Ti underlayer highly orientated can be improved crystallographic and magnetic characteristics of Co-Cr -Ta perpendicular media layer.

• 한국표면공학회지
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• 제31권5호
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• pp.278-285
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• 1998

Alloys of Ti-15Mo-5Zr-3Al(wt%) were oxidized in air between 700 and $900^{\circ}C$. It was found that the oxidation resistance is much better than that of either commercially available pure Ti-6Al-4V(wt%) alloys. The oxide scales were primarily composed of thick Ti-ox-ides which were formed by the inward diffusion of oxygen from the atmosphere. At higher temperatures a thin $\alpha$-$Al_2O_3$ layer was formed on Ti-oxides owing to the outward diffusion of Al from the base alloys. Molybdenum, the noblest metal among the alloy components, was predominantly present behind the oxide-substrate interface. Zirconium, an oxygen active metal, was present at both the oxide layer and the substrate.

• 조명전기설비학회논문지
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• 제24권3호
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• pp.14-19
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• 2010

Partial anodic oxidation of Ti-mesh with a wire diameter of ~200[${\mu}m$] produces self-aligned $TiO_2$ nanotube arrays (~50[${\mu}m$] in length) on Ti-mesh substrate. The electrolyte used for anodic oxidation was an ethylene glycol solution with an addition of 1.5 vol. % $H_2O$ and 0.2 wt. % $NH_4F$. A dye-sensitized solar cell utilizing the photoanode structure of $TiO_2$-nanotube/Ti-mesh was fabricated without a transparent conducting oxide (TCO) layer, in which Ti-mesh replaced the role of TCO. The 1.93[%] photoconversion efficiency was low, which can be attributed to both insufficient dye molecules attachment and limited electrolyte flow to dye molecules. The optimized nanotube diameter and length as well as the $TiCl_4$ treatment can improve cell performance.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 추계학술대회 논문집 전기물성,응용부문
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• pp.189-190
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• 2005

Ploycrystalline $Pb(Zr_{0.5},Ti_{0.5))O_3$ and $BaTiO_3$ powder were prepared by sol-gel process. The alumina substrate were sintered at $1400^{\circ}C$ with bottom electrode of Pt for 2 hours. The Pb(Zr0.5,Ti0.5)O3 / BaTiO3 multilayered thick films with laminating times were fabricated on alumina substrate by screening printing method. The obtained thick films were sintered at $800^{\circ}C$ with upper electrode of Ag paste for 1 hour. Structural properties of Pb(Zr0.5,Ti0.5)O3 / BaTiO3 multilayered thick films were investigated. As a result of the Differential Thermal Analysis(DTA) of Pb(Zr0.5,Ti0.5)O3, exothermic peak was observed at around 650 $^{\circ}C$. The X-ray diffraction (XRD) patterns indicated that BaTiO3 and Pb(Zr0.5,Ti0.5)O3 phases and porosities were formed in the interface of Pb(Zr0.5,Ti0.5)O3 / BaTiO3multilayered thick films.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 제36회 하계학술대회 논문집 C
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• pp.1960-1961
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• 2005

Ploycrystalline $Pb(Zr_{0.5},Ti_{0.5})O_3$ and $BaTiO_3$ powder were prepared by sol-gel process. The alumina substrate were sintered at $1400^{\circ}C$ with bottom electrode of Pt for 2 hours. The Pb(Zr0.5, Ti0.5)O3/BaTiO3 multilayered thick films with laminating times were fabricated on alumina substrate by screening printing method. The obtained thick films were sintered at $800^{\circ}C$ with upper electrode of Ag paste for 1 hour, Structural properties of Pb(Zr0.5,Ti0.5)O3/BaTiO3 multilayered thick films were investigated. As a result of the Differential Thermal Analysis(DTA) of Pb(Zr0.5,Ti0.5)O3, exothermic peak was observed at around $650^{\circ}C$. The X-ray diffraction (XRD) patterns indicated that BaTiO3 and Pb(Zr0.5,Ti0.5)O3 phases and porosities were formed in the interface of Pb(Zr0.5,Ti0.5)O3 / EaTiO3 multilayered thick films.

• 대한전자공학회논문지
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• 제27권2호
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• pp.73-80
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• 1990

Si의 기판상태, 불순물의 종류와 양, 어닐링온도 등을 달리하여 Ti-silicides를 형성시켰을 때 면 저항과 두께측정, 불순물들의 분포와 미세구조 관찰을 통하여 Ti-silicides 형성반응을 조사하였다. 기판상태, 불순물의 농도, 어닐링온도가 Ti-silicides 형성에 직접적으로 영향을 미쳤다. Amorphous Si 기판상에서 Ti-silicides가 형성되었을 때 $TiSi_2/Si$ 계면편평도가 보다 향상되었다. Poly-Si내 불순물의 농도가 $1{\times}10^{16}ions/cm^2$ 이상일 때 $TiSi_2$ 형성이 크게 억제되었고 면저항이 증가하였다. 불순물의 out-diffusion에 영향을 미치는 인자 중의 하나는 이온주입에너지에 의해 결정되는 초기 불순물의 분포였다. 이온주입 공정보다 $POCI_3$ 공정에서 불순물의 out-diffusion이 적게 나타났다.

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제53권10호
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• pp.505-509
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• 2004

The (Sr/sub 0.9/Ca/sub 0.1/)TiO₃(SCT) thin films are deposited on Pt-coated electrode(Pt/TiN/SiO₂/Si) using RF sputtering method at various substrate temperature. The optimum conditions of RF power and Ar/O₂ ratio were 140[W] and 80/20, respectively. Deposition rate of SCT thin film was about 18.75[Å/min]. The crystallinity of SCT thin films were increased with increase of substrate temperature in the temperature range of 100～500[℃]. The dielectric constant of SCT thin films were increased with the increase of substrate temperature, and changed almost linearly in temperature ranges of -80～+90[℃]. The current-voltage characteristics of SCT thin films showed the increasing leakage current as the substrate temperature increases.

• 한국분말재료학회지
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• 제21권5호
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• pp.371-376
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• 2014

In this study, modified catalytic chemical vapor deposition (CCVD) method was applied to control the CNTs (carbon nanotubes) growth. Since titanium (Ti) substrate and iron (Fe) catalysts react one another and form a new phase ($Fe_2TiO_5$) above $700^{\circ}C$, the decrease of CNT yield above $800^{\circ}C$ where methane gas decomposes is inevitable under common CCVD method. Therefore, we synthesized CNTs on the Ti substrate by dividing the tube furnace into two sections (left and right) and heating them to different temperatures each. The reactant gas flew through from the end of the right tube furnace while the Ti substrate was placed in the center of the left tube furnace. When the CNT growth temperature was set $700/950^{\circ}C$ (left/right), CNTs with high yield were observed. Also, by examining the micro-structure of CNTs of $700/950^{\circ}C$, it was confirmed that CNTs show the bamboo-like structure.