• 한국재료학회지
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• 제13권2호
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• pp.88-93
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• 2003

Co/Ti bilayer structure in Co salicide process helps to the improvement of device speed by lowering contact resistance due to the epitaxial growth of $CoSi_2$layers. We investigated the epitaxial growth and interfacial mass transport of $CoSi_2$layers formed from $150 \AA$-Co/Ti structure with two step rapid thermal annealing (RTA). The thicknesses of Ti layers were varied from 20 $\AA$ to 100 $\AA$. After we confirmed the appropriate deposition of Ti film even below $100\AA$-thick, we investigated the cross sectional microstructure, surface roughness, eptiaxial growth, and mass transportation of$ CoSi_2$films formed from various Ti thickness with a cross sectional transmission electron microscopy XTEM), scanning probe microscopy (SPM), X-ray diffractometery (XRD), and Auger electron depth profiling, respectively. We found that all Ti interlayer led to$ CoSi_2$epitaxial growth, while $20 \AA$-thick Ti caused imperfect epitaxy. Ti interlayer also caused Co-Ti-Si compounds on top of $CoSi_2$, which were very hard to remove selectively. Our result implied that we need to employ appropriate Ti thickness to enhance the epitaxial growth as well as to lessen Co-Ti-Si compound formation.

• 한국재료학회지
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• 제23권6호
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• pp.334-338
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• 2013

In this study, $BaTiO_3$ thin films were grown by RF-magnetron sputtering, and the effects of the thin film thickness on the structural characteristics of $BaTiO_3$ thin films were systematically investigated. Instead of the oxide substrates generally used for the growth of $BaTiO_3$ thin films, p-Si substrates which are widely used in the current semiconductor processing, were used in this study in order to pursue high efficiency in device integration processing. For the crystallization of the grown thin films, annealing was carried out in air, and the annealing temperature was varied from $700^{\circ}C$. The changed thickness was within 200 nm~1200 nm. The XRD results showed that the best crystal quality was obtained for ample thicknesses 700 nm~1200 nm. The SEM analysis revealed that Si/$BaTiO_3$ are good quality interface characteristics within 300 nm when observed thickness. And surface roughness observed of $BaTiO_3$ thin films from AFM measurement are good quality surface characteristics within 300 nm. Depth-profiling analysis through GDS (glow discharge spectrometer) showed that the stoichiometric composition could be maintained. The results obtained in this study clearly revealed $BaTiO_3$ thin films grown on a p-Si substrate such as thin film thickness. The optimum thickness was 300 nm, the thin film was found to have the characteristics of thin film with good electrical properties.

• 한국재료학회지
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• 제34권4호
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• pp.202-207
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• 2024

In this study, we undertook detailed experiments to increase hydrogen production efficiency by optimizing the thickness of titanium dioxide (TiO₂) thin films. TiO₂ films were deposited on p-type silicon (Si) wafers using atomic layer deposition (ALD) technology. The main goal was to identify the optimal thickness of TiO₂ film that would maximize hydrogen production efficiency while maintaining stable operating conditions. The photoelectrochemical (PEC) properties of the TiO₂ films of different thicknesses were evaluated using open circuit potential (OCP) and linear sweep voltammetry (LSV) analysis. These techniques play a pivotal role in evaluating the electrochemical behavior and photoactivity of semiconductor materials in PEC systems. Our results showed photovoltage tended to improve with increasing thickness of TiO₂ deposition. However, this improvement was observed to plateau and eventually decline when the thickness exceeded 1.5 nm, showing a correlation between charge transfer efficiency and tunneling. On the other hand, LSV analysis showed bare Si had the greatest efficiency, and that the deposition of TiO₂ caused a positive change in the formation of photovoltage, but was not optimal. We show that oxide tunneling-capable TiO₂ film thicknesses of 1~2 nm have the potential to improve the efficiency of PEC hydrogen production systems. This study not only reveals the complex relationship between film thickness and PEC performance, but also enabled greater efficiency and set a benchmark for future research aimed at developing sustainable hydrogen production technologies.

• 열처리공학회지
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• 제5권1호
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• pp.1-12
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• 1992

In order to improve adhesive force of TiN film, we sputtered titanium as interlayer before TiN deposition by Plasma Enhanced Chemical Vapour Deposition. We observed changes of hardness and adhesion at a various thickness of titanium interlayer and also examined analysis. At the critical thickness of the titanium interlayer(about $0.2{\mu}$), adhesive force of TiN films were promoted mostly. But over the critical thickness, a marked reduction of adhesive force was showed, because of the internal stress of titanium interlayer. From AES analysis, the adhesion improvement of TiN films was mainly caused by nitrogen diffusion into titanium interlayer during TiN deposition process which relieved stress concentration at TiN coating-substrate interface.

• 한국조명전기설비학회:학술대회논문집
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• 한국조명전기설비학회 2002년도 학술대회논문집
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• pp.329-334
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• 2002

This study evaporates TiO$_2$ layer thickness differently with RF sputtering method on Si Wafer(n-100). Thin film is made with the structure of Si+TiO$_2$ and Si+TiO$_2$+Al by evaporating TiN which is used as Antireflection of superintegrated semiconductor integrated circuit with Photo Catalyst. The research is performed to increase the characteristics of photon energy according to TiO$_2$ thickness and the reliability and reproducibility of TiO$_2$ thin film. Reversal of electric Permittivity values is induced by dipole polarization shown in the dielectric of thin film. Complex electric constant ($\varepsilon$$_1$, $\varepsilon$$_2$) has larger peak values as it's thickness is thinner and then it is larger according to the increase of frequency. Electric Permittivity by photon energy has large value in imaginary number and is reduced exponentially by the increase of carrier density according to that of photon energy.

• 연구논문집
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• 통권28호
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• pp.219-227
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• 1998

In order to investigate the interfacial structure between TiN and iron nitride, an AISI 4140 steel was nitrided to form a layer of thickness 15$\mum$ by DC ion nitriding, then the surface was bombarded with Ti ions and subsequently coated a TiN film of 5$\mum$ by arc ion plating method. The interfacial microstructure between TiN and iron nitride was characterized by optical microscope, SEM and XRD. So called black layer was observed in the duplex treatment. It was resulted from the decomposition of iron nitride during the bombardment. Its thickness was increased with increasing bombardment time at high bias voltage. But the thickness was greatly decreased when the iron nitride was bombarded with a nitrogen gas or at a reduced bias voltage. The adhesion strength of the top TiN coating was decreased with increasing thickness of the black layer. Furthermore, the reduced adhesion strength in this system was discussed in view of the interfacial structural relationship between TiN and iron nitride.

• 열처리공학회지
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• 제2권4호
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• pp.11-18
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• 1989

To investigate the influence of $TiCl_4$, $N_2$ inlet fraction on the TiN layer, TiN film was deposited onto the STC3 and STD11 steel from gas mixtures of $TiCl_4/N_2/H_2$ by the radio frequency plasma assisted chemical vapor deposition. The films were deposited at various $TiCl_4$, $N_2$ inlet fractions. The results showed that the film thickness was increased with $TiCl_4$ inlet fraction. However, while the thickness was increased with $N_4$ inlet fraction under 0.4 the thickness was decreased with increasing $N_2$ inlet fraction over 0.4. The density of deposited films was varied as $TiCl_4$, $N_2$ inlet fraction and its maximum value was about $5.6g/cm^3$. The contents of chlorine were increased with increasing $TiCl_4$ inlet fraction and nearly constant with increasing $N_2$ inlet fraction.

• 기술사
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• 제21권1호
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• pp.5-12
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• 1988

The purpose of this paper is to investigate on the optimum coating thickness layer of TiC-Al$_2$O$_3$ coated cemented carbide tool. Chemical Vapor Deposition (CVD) of a thick film of TiC-A1$_2$O$_3$ on a cemented carbide produces an intermediate layer, $1.5mutextrm{m}$, 4.5${\mu}{\textrm}{m}$, 7.5${\mu}{\textrm}{m}$ 10.5${\mu}{\textrm}{m}$, 4 kind of TiC between the substrate and the $1.5mutextrm{m}$ constant thick A1$_2$O$_3$ coating. Experiments were carried out with the test relationship between coating thickness and shear angle, surface roughness, cutting force, microphotograph of crater wear, flank wear, tool life. From the experimental results, it was found that the optimum coating thickness of TiC-A1$_2$O$_3$ is 6${\mu}{\textrm}{m}$. Although the coating thickness layer 9${\mu}{\textrm}{m}$. 12${\mu}{\textrm}{m}$ have a much loger tool wear than an 3${\mu}{\textrm}{m}$, 6${\mu}{\textrm}{m}$ coating tool in cutting condition feed 0.05mm/rev, and the condition of feed 0.2mm/rev, 0.3mm/rev has upon in the shot time phenomenon of chipping.

• Bulletin of the Korean Chemical Society
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• 제23권5호
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• pp.741-744
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• 2002

Single phase of multicomponent oxide ZrTiO4 film could be prepared through surface sol-gel route simply by coating the mixture of 100 mM zirconium butoxide and titanium butoxide on $Pt/Ti/SiO_2Si(100)$ substrate, following pyro lysis at $450^{\circ}C$, and annealing it at 770 $^{\circ}C.$ The dielectric constant of the film was reduced as the film thickness decreased due to of the interfacial effects caused by layer/electrode and a few voids inside the multilayer. However, the dielectric property was independent of applied dc bias sweeps voltage (-2 to +2 V).The dielectric constant of bulk film, 31.9, estimated using series-connected capacitor model was independent of film thickness and frequency in the measurement range, but theoretical interfacial thickness, ti, was dependent on the frequency. It reached a saturated ti value, $6.9{\AA}$, at high frequency by extraction of some capacitance component formed at low frequency range. The dielectric constant of bulk ZrTiO4 pellet-shaped material was 33.7 and very stable with frequency promising as good applicable devices.

• Rapid Communication in Photoscience
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• 제2권1호
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• pp.1-8
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• 2013

Transparent $TiO_2$ films in various thicknesses were prepared by sol-gel and MOCVD method, respectively, and their photocatalytic activities in decomposing gaseous 2-propanol were evaluated. The surfaces and grain structures of the prepared films were characterized by FESEM, XRD, and AFM. It was found that the photocatalytic activities of $TiO_2$ films were greatly dependent on the film thickness and surface roughness: The photocatalytic activity increases with the increase of film thickness, while it decreases with the increase of surface roughness. We have proposed that these phenomena originate from the transfer of photogenerated electron and hole pairs from the bulk to the surface of $TiO_2$ film. Several experimental evidences supporting this mechanism have also been provided.