• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2009.06a
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• pp.154-154
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• 2009

Cr capping layer를 이용하여 Titanium germanide의 열적 안정성을 향상시키는 연구를 수행하였다. n-type Ge(100) 기판 위에 전자빔 증착기를 이용하여 30nm 두께의 Ti와 Cr capping layer를 증착하고 $400\;^{\circ}C$에서 $800\;^{\circ}C$까지 30초간 N2 분위기로 급속 열처리하여 Ti germanide를 형성하였다. XRD결과로부터 Cr capping layer의 유무에 관계 없이 Ti germanide가 형성된 것을 관찰할 수 있었다. Ge 기판 위에 CTLM 패턴을 형성하고 실험을 진행하여 Ti germanide의 I-V 측정 데이터를 통해 Ohmic 특성을 알아보았고, contact resistance, sheet resistance, specific contact resistance를 구하였다.

• The Journal of Korean Academy of Prosthodontics
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• v.38 no.3
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• pp.358-359
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• 2000

Statement of problem. Confusion about the relationship of surface characteristics of implant to osteoblast cell attachment. Purpose. This study attempted to bone cell attachment to the implant surface which was modified by heat. Material and methods. Commercially pure titanium grade 2, $4{\times}4mm$ sheet 40 pieces were treated for 10 minutes with ultrasonic cleaner with methylethyl ketone, ethanol, deionized distilled water, and half of the specimen 20 pieces were heat treated in $980^{\circ}C$ for 15 minutes. All 40 specimens were autoclaves. Total 6 dishes were prepared, 3 dishes were for control group, and the other 3 dishes were for heat treatment. In fourth day, cell account was done. Conculsion. The change of surface characterization by heat treatment could affect the cell attachment in the early stage however, the change of surface characterization would not be prolonged.

• Journal of Navigation and Port Research
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• v.34 no.4
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• pp.299-304
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• 2010

In this paper, the EM wave absorber was developed for the 94-GHz detecting radar system. To analysis an EM wave absorber in millimeter wave band, we fabricated three absorber samples using carbon black and titanium dioxide and permalloy with chlorinated polyethylene. After measuring the complex relative permittivity, the absorption characteristics are simulated by 1D FDTD according to different thicknesses of less than 1.0 mm. Then, the EM wave absorber was fabricated based on the FDTD simulation. As a result, the measured results agreed well with the simulated ones, and the developed EM wave absorber with a thickness of 0.7 mm had the desired absorption characteristics of more than 14 dB in the frequency range of the 94-GHz band.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.31 no.2
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• pp.77-85
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• 1999

A study on the thermal stability of commonly used six fillers, such as titanium dioxide, silica, ground calcium carbonate, zeolite, and, clay, showed that most fillers except titanium dioxide were strongly effected by heat treatment. Therefore, the present methods for determination of ash in paper give weight loss due to thermal decomposition of fillers. It was found that a paper ashing method at a temperature of 40$0^{\circ}C$ allows most fillers in their original and undecomposed from. Results presented in this paper also show that X-ray diffraction can be used for qualitative determination of mixed fillers and coating pigments in a paper sheet.

• Transactions of Materials Processing
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• v.31 no.4
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• pp.214-228
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• 2022

The yield criterion, or called yield function, plays an important role in the study of plastic working of a sheet because it governs the plastic deformation properties of the sheet during plastic forming process. In this paper, we propose a novel anisotropic yield function useful for describing the plastic behavior of various anisotropic sheets. The proposed yield function includes the anisotropic version of the second stress invariant J₂ and the third stress invariant J₃. The anisotropic yield function newly proposed in this study is as follows. F(J₂)+ αG(J₃)+ βH (J₂ × J₃) = k^m The proposed yield function well explains the anisotropic plastic behavior of various sheets by introducing the parameters α and β, and also exhibits both symmetrical and asymmetrical yield surfaces. The parameters included in the proposed model are determined through an optimization algorithm from uniaxial and biaxial experimental data under proportional loading path. In this study, the validity of the proposed anisotropic yield function was verified by comparing the yield surface shape, normalized uniaxial yield stress value, and Lankford's anisotropic coefficient R-value derived with the experimental results. Application for the proposed anisotropic yield function to aluminum sheet shows symmetrical yielding behavior and to pure titanium sheet shows asymmetric yielding behavior, it was shown that the yield curve and yield behavior of various types of sheet materials can be predicted reasonably by using the proposed new yield anisotropic function.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.27 no.11
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• pp.725-729
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• 2014

In this study, a transparent conductive oxide (TCO)-less dye-sensitized solar cells (DSSCs) was fabricated by using titanium (Ti) electrode to replace the Fluorine-doped tin oxide (FTO) for the reduction of manufacturing cost. Ti film was formed by electron beam evaporation method and the results showed the sheet resistance of Ti electrodes with a thikness of 500 nm similar to FTO. In case of power conversion efficiency (PCE), a DSSC with Ti electrodes showed a lower value than that with FTO by 0.38%. For the investigation of the difference, the DSSCs were measured and analyzed by using electrochemical impedance analyzer (EIS).

• Proceedings of the IEEK Conference
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• 2003.07b
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• pp.671-674
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• 2003

본 논문에서는 Cobalt interlayer 와 Titanium Nitride(TiN) capping layer를 Ni SALICIDE의 단점인 열 안정성과 sheet resistance 와 series 저항을 감소시키는데 적용하여 0.lum 급 CMOS 소자의 특성을 연구하였다. 첫째로, Ni/Si 의 interface 에 Co interlayer 를 증착하여 Nickel Silicide의 단점인 열 안정성 평가인 700℃, 30min의 furnace annealing 후에 낮은 sheet resistance와 누설전류를 줄일 수 있었다. 두번째로, TiN caping layer를 적용하여 실리사이드 형성시 산소와의 반응을 막아 실리사이드의 표면특성을 향상시켜 누설전류의 특성을 개선하였다. 결과적으로 소자의 구동전류 향상, 누설전류 저하, 낮은 면저항으로 소자의 특성을 개선하였다.

• Proceedings of the KIEE Conference
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• 1987.07a
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• pp.454-457
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• 1987

Formation of the titanium silicides was performed by the furnace annealing. Ti-silicide was formed by reacting Ti films with singlecrystalline silicon in vacuum or nitrogen ambient in the temperature range $500{\sim}900^{\circ}C$. The Ti-Si interaction in such films was investigated by using X-ray diffraction, and sheet resistance measurements. It was found that the dorminant crystal phase of silicide formed during annealing at $600{\sim}700^{\circ}C$ was TiSi, and $TiSi_2$ phase is associated with a very low sheet resistance(<$2{\Omega}/{\Box}$).

• Transactions of Materials Processing
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• v.24 no.1
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• pp.5-12
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• 2015

In the current study, fundamental deep drawing characteristics of Ti-6Al-4V alloy sheets were investigated to establish the effect of processing conditions on large size square deep drawn cups. To accomplish this study, FE-simulations (Abaqus) were performed to determine optimum blank size, friction coefficient, the gap between punch and die, etc. The simulated processing parameters were verified experimentally. Based on the FE-simulation results, deep drawing was performed with various blank holding loads and sample sizes. In order to improve the formability of Ti-6Al-4V sheet, various lubricant methods were evaluated. Tensile tests and thickness measurements were conducted on the formed sheets. Processing parameters including blank holding force, lubricants, and optimum blank size, were selected to achieve improved drawing quality. With the optimum processing condition, a $200mm{\times}200mm$ cup was deep drawn successfully.

• Korean Journal of Materials Research
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• v.10 no.1
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• pp.90-96
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• 2000

The effects of the type and thickness of underlayers on the crystallographic texture and the sheet resistance of aluminum thin films were studied. Sputtered Ti and Ti/TiN were examined as the underlayer of the aluminum films. The texture and the sheet resistance of the metal thin film stacks were investigated at various thicknesses of Ti or TiN, and the sheet resistance was measured after annealing at $400^{\circ}C$ in an nitrogen ambient. For the Ti underlayer, the minimum thickness to obtain excellent texture of aluminum <111> was 10nm, and the sheet resistance of the metal stack was greatly increased after annealing due to the interdiffusion and reaction of Al and Ti. TiN between Ti and Al could suppress the Al-Ti reaction, while it deteriorated the texture of the aluminum film. For the Ti/TiN underlayer, the minimum Ti thickness to obtain excellent texture of aluminum <111> was 20nm, and the minimum thickness of TiN to function as a diffusion barrier between Ti and Al was 20nm.