• Journal of the Korean Institute of Telematics and Electronics A
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• v.33A no.3
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• pp.117-125
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• 1996

The variation of the interfacial and the electrical properties of SiO$_{2}$TiW layers as a function of anneal temperature was extensively investigated. During the deposition of SiO$_{2}$ on TiW chemical bonds such as SiO$_{2}$, TiW, WO$_{3}$, WO$_{2}$ TiO$_{2}$ Ti$_{2}$O$_{5}$ has been created at the SiO$_{2}$/TiW interface. At the anneal temperature of 300$^{\circ}C$, WO$_{3}$ and TiO$_{2}$ bonds started to break due to the reduction phenomena of W and Ti and simultaneously the metallic W and Ti bonds started to create. Above 500$^{\circ}C$, a part of Si-O bonds was broken and consequently Ti/W silicide was formed. Form the current-voltage characteristics of Al/Sico$_{2}$(220$\AA$)/TiW antifuse structure, it was found that the breakdown voltage of antifuse device wzas decreased with increasing annealing temperature for SiO$_{2}$(220$\AA$)/TiW layer. When r, the insulating property of antifuse device of the deterioration of intermetallic SiO$_{2}$ film, caused by the influw of Ti and W.W.

• Journal of the Korean Applied Science and Technology
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• v.29 no.3
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• pp.495-502
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• 2012

Using the Sedimentation method it's possible to get $TiO_2$ particle from which by this research, $TiO_2$ particle was produced. The parameter in the kind of the temperature and the alcohol solvent used $TiO_2$ particle production investigated crystal structure of $TiO_2$ particle and the influence exerted on the size of the particle and the form. After scanning electron microscope (SEM) analyzed methyl alcohol, iso-propylalcohol and tert-butylalcohol used by a solvent at the $TiO_2$ particle production, iso-propylalcohol was most effective. And after an thermogravimetric analyzer method was used, the anatase structure was maintained $500^{\circ}C$ by $200^{\circ}C$, but it was converted by the rutile structure by $800^{\circ}C$.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.8 no.4
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• pp.563-566
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• 1998

$BaTiO_3$ fine particles were prepared by hydrothermal process from titanium tetra-isoproproxide ($Ti(OiPr)_4$) and barium hexa-hydroxide ($Ba(OH)_2{cdot}8H_2O$) as raw materials. The fine particles were obtained at the temperature range of 160 to $185^{\circ}C$. The properties of $BaTiO_3$ particles were studied as a function of various parameters such as reaction temperature, reaction time and Ba/Ti ratio, etc. The average particle size of $BaTiO_3$ increased with increasing reaction temperature and time. After hydrothermal treatment at $170^{\circ}C$ for 8 h, the average particle size of $BaTiO_3$ was about 30 nm and the particle size distribution was narrow.

• Journal of Technologic Dentistry
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• v.26 no.1
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• pp.97-104
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• 2004

A new Ti-10Ta-10Nb alloy has designed and examined some possibility of forming more passive oxide film by oxidation treatment which is closely related to corrosion resistance and biocompatibility. Ti-6Al-4V and Ti-10Ta-10Nb alloys were prepared by consumable vacuum arc melting and homogenized at 1050$^{\circ}C$ for 24hours. Alloy specimens were oxidized at the temperature range of 400 to 750$^{\circ}C$ for 30minutes, and the oxide films on Ti alloys were analysed by optical microscope, SEM, XPS and TGA. Cytotoxicity test was performed in MTT assay treated L929 fibroblast cell culture by indirect method. It is found out that the oxide film on Ti-10Ta-10Nb alloy is denser and thinner compared to Ti-6Al-4V alloy. The weight gain during the oxidation was increased rapidly at the temperature above 650$^{\circ}C$ for Ti-6Al-4V alloy and above 700$^{\circ}C$ for Ti-10Ta-10Nb alloy respectively. It was analysed that the passive film of the Ti alloys consisted of TiO2 through X-ray photoelectron spectroscopy (XPS) analysis. It is found out by cytotoxicity test that moderate oxidation treatment lowers cell toxicity, and Ti-10Ta-10Nb alloy showed better result compared to Ti-6Al-4V alloy.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.20 no.8
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• pp.706-710
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• 2007

Ti-containing amorphous carbon (a-C:Ti) films shows attractive mechanical properties such as low friction coefficient, good adhesion to various substrate and high wear resistance. The incorporation of titanium in a-C films is able to improve the electrical conductivity, friction coefficient and adhesion to various substrates. In this study, a-C:Ti films were depositied on Si wafer by closed-field unbalanced magnetron (CFUBM) sputtering system composed two targets of carbon and titanium. The tribological properties of a-C:Ti films were investigated with the increase of DC bias voltage from 0 V to - 200 V. The hardness and elastic modulus of films increase with the increase of DC bias voltage and the maximum hardness shows 21 GPa. Also, the coefficient of friction exhibites as low as 0.07 in the ambient. In the result, the a-C:Ti film obtained by CFUBM sputtering method improved the tribological properties with the increase of DC bias volatage.

• Journal of the Korean Ceramic Society
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• v.28 no.9
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• pp.721-729
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• 1991

SnO2-TiO2(Pt or Pd), as raw material for hydrocarbon gas sensors, was prepared by a coprecipitation method. The SnO2-TiO2-based thick film gas sensors were made by screen printing technique. The titanium dioxide synthesized was shown to be anatase structure from XRD peaks and was transformed to rutile structure between 700$^{\circ}C$ and 1000$^{\circ}C$. Titanium dioxide in SnO2-TiO2 thick films devices plays a very important role in the enhancement of the sensitivity to CH4 and C4H10. In the case of SnO2-TiO2(Pt) sensors, titanium dioxide that was rutile structure enhanced the sensitivity of the thick film to CH4. Platinum added to the raw powder at coprecipitation (as chloroplatinic acid VI hydrate) improved the gas sensitivity to hydrocarbon gases. Therefore, it is expected that the SnO2-TiO2(Pt) thick film sensors fabricated in this experiment could be put into practical use as LPG (primary component : C4H10 and C3H8) and LNG (primary component : CH4) sensors.

• Korean Journal of Metals and Materials
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• v.50 no.11
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• pp.801-808
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• 2012

TiAlCN coatings with various C contents were synthesized by unbalanced magnetron sputtering. The characteristics, the crystalline structure, surface morphology, hardness, and friction coefficient of the coatings as a function of the C content were investigated by X-ray diffraction (XRD), atomic force microscopy (AFM), a microhardness tester, and a wear test. In addition, their corrosion behaviors in a deaerated 3.5 wt% NaCl solution at $40^{\circ}C$ were investigated by potentiodynamic polarization tests. The results indicated that the $Ti_{14.9}Al_{15.5}C_{30.7}N_{38.9}$ coating had the highest hardness, elastic modulus, and a plastic deformation resistance of 39 GPa, 359 GPa, and 0.55, respectively, and it also had the lowest friction coefficient of approximately 0.26. Comparative evaluation of the TiAlCN coatings indicated that a wide range of coating properties, especially coating hardness, could be obtained by the synthesis methods and processing variables. The microhardness of the coatings was much higher than that from previously reported coating using similar magnetron sputtering processes. It was almost as high as the microhardness measured from the TiAlCN coatings (~41 GPa) synthesized using an arc ion plating process. The potentiodynamic test showed that the corrosion resistance of the TiAlCN coatings was significantly better than the TiAlN coatings, and their corrosion current density ($i_{corr}$), corrosion potentials ($E_{corr}$) and corrosion rate decreased with an increasing C content in the coatings. The much denser microstructure of the coatings due to the increased amount of amorphous phase with increasing C contents in the coatings could result in the the improved corrosion resistance of the coatings.

• Journal of Welding and Joining
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• v.27 no.2
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• pp.38-43
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• 2009

In this study, we investigated photocatalytic ability of plasma sprayed $TiO_2$ and Ag sputtering $TiO_2$(Ag-$TiO_2$) coatings. A sputtering processes were adopted to coat the surface of $TiO_2$ with Ag(99.99%). Ag was sputtered at 10mA, 450V for $1{\sim}11$ seconds. $TiO_2$ and Ag-$TiO_2$ coatings were heat-treated at 250, 300, 350, $400^{\circ}C$ for $0{\sim}240$seconds. Photoelectrical conductivity was measured by four-point probe, and photodegradation was calculated by UV-V is spectrometer. Microstructure observation of $TiO_2$ and Ag-$TiO_2$ coatings were investigated by SEM. Crystal structure of $TiO_2$ and Ag-$TiO_2$ coatings were investigated by XRD. Qualitative analyses of $TiO_2$ and Ag-$TiO_2$ coatings were conducted by EDX. When $TiO_2$ coatings were heat-treated at $350^{\circ}C$ for 30 sec, photoelectrical conductivity and photodegradation were best. And in XRD analysis result, (101)/(110) relative intensity ratio of $TiO_2$(rutile) was comparably changed with photoelectrical conductivity. When Ag-$TiO_2$ coatings were heat-treated at $350^{\circ}C$ for 30 [sec] after sputtering Ag for 7 sec, Photoelectrical conductivity and photodegradation are best. Surface of coatings in such condition has very small and uniform Ag particles.

• Journal of Korean Society of Environmental Engineers
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• v.27 no.9
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• pp.932-938
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• 2005

[ $TiO_2$ ] nanoparticles were prepared from the precipitation in $TiCl_4$ and the sol-gel profess in $Ti(OC_3H_7)_4$ as starting materials with various synthetic conditions. The samples were characterized by XRD, SEM, and TEM testing techniques. The photocatalytic degradation of congo red has been investigated in $TiO_2/UV$ process to evaluate photocatalytic activities for the samples. $TiO_2$ nanoparticles calcined at $400^{\circ}C$ had the best photocatalytic activity with the rate constant of the degradation of congo red as $0.0319\;min^{-1}$. The rate constant of $TiO_2$ photocatalysts was increased with the calcination temperature under $400^{\circ}C$ and decreased with the calcination temperature upper $400^{\circ}C$. In the case of $TiO_2$ photocatalysts, the photocatalytic activity wasn't greatly affected by the frequencies of usage. In the similar synthesis condition, the degradation efficiency of the $TiO_2$ particle prepared by $TiCl_4$ was increased to 8.8%, when the rate was compared with the sample prepared by $Ti(OC_3H_7)_4$. The photocatalytic activities of $TiO_2$ photocatalysts synthesized by $Ti(OC_3H_7)_4$ with various conditions were also discussed.

• Proceedings of the Korean Vacuum Society Conference
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• 2000.02a
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• pp.77-77
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• 2000

Titanium oxide (TiO2) thin films have valuable properties such as a high refractive index, excellent transmittance in the visible and near-IR frequency, and high chemical stability. Therefore it is extensively used in anti-reflection coating, sensor, and photocatalysis as electrical and optical applications. Specially, TiO2 have a high dielectric constant of 180 along the c axis and 90 along the a axis, so it is highlighted in fabricating dielectric capacitors in micro electronic devices. A variety of methods have been used to produce patterned self-assembled monolayers (SAMs), including microcontact printing ($\mu$CP), UV-photolithotgraphy, e-beam lithography, scanned-probe based micro-machining, and atom-lithography. Above all, thin film fabrication on $\mu$CP modified surface is a potentially low-cost, high-throughput method, because it does not require expensive photolithographic equipment, and it produce micrometer scale patterns in thin film materials. The patterned SAMs were used as thin resists, to transfer patterns onto thin films either by chemical etching or by selective deposition. In this study, we deposited TiO2 thin films on Si (1000 substrateds using titanium (IV) isopropoxide ([Ti(O(C3H7)4)] ; TIP as a single molecular precursor at deposition temperature in the range of 300-$700^{\circ}C$ without any carrier and bubbler gas. Crack-free, highly oriented TiO2 polycrystalline thin films with anatase phase and stoichimetric ratio of Ti and O were successfully deposited on Si(100) at temperature as low as 50$0^{\circ}C$. XRD and TED data showed that below 50$0^{\circ}C$, the TiO2 thin films were dominantly grown on Si(100) surfaces in the [211] direction, whereas with increasing the deposition temperature to $700^{\circ}C$, the main films growth direction was changed to be [200]. Two distinct growth behaviors were observed from the Arhenius plots. In addition to deposition of THe TiO2 thin films on Si(100) substrates, patterning of TiO2 thin films was also performed at grown temperature in the range of 300-50$0^{\circ}C$ by MOCVD onto the Si(100) substrates of which surface was modified by organic thin film template. The organic thin film of SAm is obtained by the $\mu$CP method. Alpha-step profile and optical microscope images showed that the boundaries between SAMs areas and selectively deposited TiO2 thin film areas are very definite and sharp. Capacitance - Voltage measurements made on TiO2 films gave a dielectric constant of 29, suggesting a possibility of electronic material applications.