• Journal of the Korean institute of surface engineering
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• v.45 no.3
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• pp.106-110
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• 2012

Oblique angle deposition (OAD) is a physical vapor deposition where incident vapor flux arrives at non-normal angles. It has been known that tilting the substrate changes the properties of the film, which is thought to be a result of morphological change of the film. In this study, OAD has been applied to prepare single and multilayer TiN films by cathodic arc deposition. TiN films have been deposited on cold-rolled steel sheets and stainless steel sheet. The deposition angle as well as substrate temperature and substrate bias was changed to investigate their effects on the properties of TiN films. TiN films were analyzed by color difference meter, scanning electron microscopy, nanoindenter and x-ray diffraction. The color of TiN films was not much changed according to the deposition conditions. The slanted and zigzag structures were observed from the single and multilayer films. The relation between substrate tilting angle (${\alpha}$) and the growth column angle (${\beta}$) followed the equation of $tan{\alpha}=2tan{\beta}$. The indentation hardness of TiN films deposited by OAD was low compared with the ones prepared at normal angle. However, it has been found that $H^3/E^2$ ratio of 3-layer TiN films prepared at OAD condition was a little higher than the ones prepared at normal angle, which can confirm the robustness of prepared films.

• Journal of the Korean institute of surface engineering
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• v.28 no.6
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• pp.343-351
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• 1995

Titanium nitride films have been prepared on various substrates (silicon wafer, HSS) by cathode arc ion plating process to measure microhardness, adhesion and wear-resistant behaviors by changing the substrate bias voltages (0∼-300V), thickness and roughness. Microhardnesses were measured by micro vickers hardness tester, the adhesion strengths were evaluated by acoustic signals through the scratch test with incremental applied load. As the substrate bias voltages were increased, the ｛111｝ orientation was predominant, the microhardnesses and adhesion strengths of tool steel were observed to be stronger than those of without subatrate bias voltage. Adhesion strengths of the substrate bias were 4-7 times higher than those of without the substrate bias, confirmed by SEM with EDX. Wear resistances were used pin-on-disk tribotester and TiN costing reduced the abrasive wear. As the substrate bias was increased, the weight loss and the friction coefficient was decreased.

• Korean Journal of Materials Research
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• v.2 no.2
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• pp.110-118
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• 1992

When CVD-W films deposited on the reactively sputter-deposited TiN(${\circled1}$), the $NH_3$-RTP (rapid themal processed) TiN(${\circled2}$), and the furnace-annealed TiN submitate (${\circled3}$) by $SiH_4$, reduction, deposition rate is in the order of ${\circled1}>{\circled2}>{\circled3}$ and incubation period of W nucleation is in the order of ${\circled1}{\leq}{\circled2}<{\circled3}$. The longest incubation period of nucleation and lowest deposition rate for the CVD-W on the annealed TiN is due to the incorporation of oxygen from the nitrogen ambient containing some oxygen as contaminant into the TiN film. The higher W deposition rate and the lower incubation period of W nucleation on the RTP-TiN substrate in comparison with those on the sputtered TiN substrate seem to be due to a negative effect of the high compressive stress of the RTP-TiN on the nucleation and growth of W. Also the thickness uniformity of the W film deposited on the TiN substrate by $SiH_4$ reduction turns out to be better than that by $H_2$ reduction.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.61 no.4
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• pp.585-589
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• 2012

The characteristics of interface layer and the effect of mole fraction of inlet gas mixture($B_2H_6/H_2/N_2/TiCl_4$) on the microstructure of Ti(B,N) films were studied by microwave plasma hot filament CVD process. Ti(B,N) films were deposited on a substrate(STD-61) to develop a high performance of resistance wear coating tool. Ti(B,N) films were obtained at a gas pressure of 1 torr, bias voltage of 300 V and substrate temperature of $480^{\circ}C$ in $B_2H_6/H_2/N_2/TiCl_4$gas system. It was found that TiN, $TiB_2$, TiB and hexagonal boron nitride(h-BN) phases exist in thin layer on the STD-61.

• Journal of the Korean Society for Heat Treatment
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• v.4 no.4
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• pp.1-14
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• 1991

In PECVD(Plasma-Enhanced Chemical Vapor Deposition) process, titanium nitride is thin and its adhesion is poor for the protective coatings. Therefore it has been studied that intermediate layer forms between substrate and TiN thin film. Using R.F. plasma nitriding, nitride layer was first formed, then TiN thin film coated by PECVD. The chemical composition of the coatings has been characterized using AES, EDS and their crystallographic structure by means of XRD. Mechanical properties such as microhardness and film adhesion have also been determined by vickers hardness test, scratch test and indentation test. As a result, there was no difference in chemical composition and structure between the TiN deposition only and the composite of TiN deposition on nitrided steel. It was found that nitrided substrate increased the hardness of TiN coatings and was beneficial in preventing the plastic deformation in the substrate. Therefore the effective load bearing capacity of the TiN coatings on nitrided steel was increased and their adhesion was improved as well. According to the results of this study, the processes that lead to the formation of composite layers characterized by good working properties, i.e., high microhardness, adhesion and resistance to deformation.

• Journal of Powder Materials
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• v.22 no.5
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• pp.326-330
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• 2015

In this study, we demonstrate the photoelectrochromic devices composed of $TiO_2$ and $WO_3$ nanostructures prepared by anodization method. The morphology and the crystal structure of anodized $TiO_2$ nanotubes and $WO_3$ nanoporous layers are investigated by SEM and XRD. To fabricate a transparent photoelectrode on FTO substrate, a $TiO_2$ nanotube membrane, which has been detached from Ti substrate, is transferred to FTO substrate and annealed at $450^{\circ}C$ for 1 hr. The photoelectrode of $TiO_2$ nanotube and the counter electrode of $WO_3$ nanoporous layer are assembled and the inner space is filled with a liquid electrolyte containing 0.5 M LiI and 5 mM $I_2$ as a redox mediator. The properties of the photoelectrochromic devices is investigated and Pt-$WO_3$ electrode system shows better electrochromic performance compared to $WO_3$ electrode.

• Journal of the Korean Vacuum Society
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• v.17 no.3
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• pp.211-214
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• 2008

GaN-based light-emitting diodes (LEDs) of a 405 nm wavelength have been fabricated on a sapphire substrate by metal organic chemical vapor deposition (MOCVD). In order to reflect the photons, which are generated in the InGaN active region and emitted to the backside, to the front surface, a reflection layer was deposited onto the back of the substrate. Aluminum was used as the reflection layer and Al was deposited on the sample followed by Ti evaporation for firm adhesion of the reflection layer to the substrate. The light extraction efficiency was enhanced 52 % by adoption of the Ti-Al reflection layer.

• Journal of Powder Materials
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• v.15 no.2
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• pp.101-106
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• 2008

The objective of the present study is to investigate the increase in the functional characteristics of a substrate by the formation of a thin coating layer. Thin coating layers of $Ti_5Si_3$ have high potential because $Ti_5Si_3$ exhibits high hardness. Shock induced reaction synthesis is an attractive fabrication technique to synthesize uniform coating layer by controlling the shock wave. Ti and Si powders to form $Ti_5Si_3$ using shock induced reaction synthesis, were mixed using high-energy ball mill into small scale. The positive effect of this technique is highly functional coating layer on the substrate due to ultra fine substructure, which improves the bonding strength. These materials are in great demand as heat resisting, structural and corrosion resistant materials. Thin $Ti_5Si_3$ coating layer was successfully recovered and showed high Vickers' hardness (Hv=1183). Characterization studies on microstructure revealed a fairly uniform distribution of powders with good interfacial integrity between the powders and the substrate.

• Tribology and Lubricants
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• v.37 no.2
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• pp.54-61
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• 2021

The effect of the sand blasting before TiAlN coating in the manufacture of WC hard metal alloy tips have been studied. For four different tips, according to the status of processing of the sand blasting and the coating, residual stress measurement by X-ray diffraction and several tests for mechanical properties have been conducted. The results suggest that there was no difference in static mechanical properties, such as hardness, surface roughness and elastic modulus, between two coatings. Furthermore, compressive residual stress was generated equally on their surfaces. Additionally, the compressive residual stress in substrate WC was found to increase greatly when subjected to sand blasting treatment. However, the compressive residual stress decrease after coating regardless of sand blasting treatment. Nevertheless, it is confirmed that the compressive residual stress generated in the coating after sand blasting is less than that in the non-sandblasting coating. This was attributed to the plastic deformation occurring in the WC substrate during coating after sand blasting. In contrast to the scratch test results, sand blasting was assumed to have a negative effect on the adhesion between the coating and substrate. This is because there is a high possibility of microcracks due to plastic deformation in the WC substrate under the coating after sand blasting.

• 한국신재생에너지학회:학술대회논문집
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• 2007.06a
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• pp.309-312
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• 2007

Sputter deposition followed by surface treatment was studied using reactive RF plasma as a method for preparing titanium oxide($TiO_{2}$) films on indium tin oxide(ITO) coated glass substrate for dye-sensitized solar cells(DSSCs). Anatase structure $TiO_{2}$ films deposited by reactive RF magnetron sputtering under the conditions of $Ar/O_{2}$(5%) mixtures, RF power of 600W and substrate temperature of $400^{\circ}C$ were surface-treated by inductive coupled plasma(ICP) with $Ar/O_{2}$ mixtures at substrate temperature of $400^{\circ}C$, and thus the films were applied to the DSSCs, The $TiO_{2}$ Films made on these exhibited the BET specific surface area of 95, the pore volume of $0.3cm^{2}$ and the TEM particle size of ${\sim}25$ nm. The DSSCs made of this $TiO_{2}$ material exhibited an energy conversion efficiency of about 2.25% at $100mW/cm^{2}$ light intensity.