• Journal of Sensor Science and Technology
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• v.13 no.3
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• pp.195-198
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• 2004

For a diffusion barrier against copper, tantalum nitride films have been deposited on $SiO_{2}$ by atomic layer deposition (ALD), using PEMAT(Pentakis(ethylmethylamino)tantalum) and $NH_{3}$ as precursors, Ar as purging gas. The deposition rate of TaN at substrate temperature $250^{\circ}C$ was about $0.67{\AA}$ per one cycle. The stability of TaN films as a Cu diffsion barrier was tested by thermal annealing for 30 minutes in $N_{2}$ ambient and characterized through XRD, sheet resistance, and C-V measurement(Cu($1000{\AA}$)/TaN($50{\AA}$)/$SiO_{2}$($2000{\AA}$)/Si capacitor fabricated), which prove the TaN film maintains the barrier properties Cu below $400^{\circ}C$.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.3
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• pp.1308-1312
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• 2011

CCFL(Cold Cathode Fluorescent Lamp)for BLU of LCD and special lighting has been widely utilized. The removal of oxide film formed on electrode of CCFL in manufacturing process is required. In this pape Plasma treatment was carried out to remove the oxide film. To ensure the optimum process, the analysis of sheet resistance, XRD, AFM and solder test was conducted. A minimum sheet resistance and the maximum percentage of the solder coverage ratio were measured in optimal process conditions such as plasma power consumption 600W and processing time of 70 seconds. As the plasma treatment is confirmed to be due to removal of copper oxide, this process is expected to be used as a treatment of electrode for CCFL.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.4 no.4
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• pp.28-33
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• 2005

Recently, trends of TFT-LCD toward larger scale and thinner thickness continue. so, demands of Light Guide Panel (LGP) which is to substitute for prism sheet are appeared. Functions of LGP obtaining polarization of light of the prism sheet as well as the incidence and reflection of light are demanded. This prism type LGP to complete functions of the existing LGP and polarization at once must be supported by micro machining technology of LGP surface. In this research, the machining characteristics of the various materials were analysed by shaping using V-shaped single crystal diamond tool. The characteristics are machined surface, machining force due to the variation of cutting depth. Used specimens are engineering materials, which are 6:4 brass, oxygen-free copper, Al6061, PC, PMMA. The FFT analysis of the measured cutting force was conducted. The cutting characteristics were analyzed and the optimum cutting conditions with materials were established.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.19 no.3
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• pp.250-254
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• 2006

Hetero-junction sheet actuator composed of carbon nanotubes and $V_{2}O_5$ nanowires were demonstrated in a bimetal configuration. The successive filtration of $V_{2}O_5$ nanowire solution followed by carbon nanotube dispersed water solution in the same way produced a dark-gray colored sheet. A significant actuation was observed in sodium chloride electrolyte solution with a bending direction to the carbon nanotube side at the positive bias voltage against the copper counter-electrode. As the frequency of the applied voltage increased, the amplitudes decreased, indicating a rather slow response of the hetero-film actuator in the electrolyte solution. The hybrid structure enabled an easy fabrication of the film actuator with the enhanced efficiencies.

• Journal of radiological science and technology
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• v.44 no.6
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• pp.615-621
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• 2021

In the medical field, radiation provides information for the diagnosis and treatment of diseases. As the use of radiation increases and the risk of exposure increases, interest in radiation protection is also rapidly increasing. Lead shielding material is mainly used, which has a risk of lead poisoning and absorption into the body. Tungsten mixed filament shielding sheets were fabricated with a size of 70 × 70 mm and a thickness of 1, 2, and 4 mm by using a 3D printer. In the general shooting experiment, the thickness of the shielding sheet is 1 ~ 5mm, the tube voltage is 60, 80, 100, 120 kVp and the tube current is 20, 40 mAs. In general photography, Tungsten showed better shielding rate compared to Brass, Copper, and Lead protective tools under all irradiation conditions, and in particular, Tungsten 5 mm showed 100% shielding rate. The 3D-printed tungsten mixed filament shielding is expected to be used as a new shield that can replace the existing lead protection tools as it shows a better shielding rate than the existing lead protection tools in Radiography.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.29 no.4
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• pp.277-284
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• 2018

This paper reports the transparent electrode, which would be applied to transparent displays and smart glasses. Herein, a squared metal mesh with the most widely used copper wire in microwaves is studied for the alternating thin-film-type transparent and conducting indium tin oxide(ITO), with a low conductivity(sheet resistance > $5{\Omega}/sq.$). The electromagnetic performance of a patch antenna with metal mesh is analyzed. This paper presents the results of the optical(OT, optical transparent) and electrical(sheet resistance) characteristics of a squared metal mesh, which is a basic design. To improve the OT, copper wire(w=0.2 mm) is used in fabricating the squared metal mesh and the relationship between the OT and the antenna performance(radiation gain, radiation pattern) was analyzed according to the mesh size(l=1, 2 mm). The measurement results show that the antenna performance and the optical characteristic are in inverse proportion to each other. In real applications, the optical and electrical characteristics, and the costs of production are to be considered.

• Journal of The Korean Society of Clinical Toxicology
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• v.4 no.2
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• pp.175-179
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• 2006

Welders are exposed to a number of hazards including metal fumes, toxic gases, electricity, heat, noise, and radiation such as ultraviolet and infrared light. We encountered a patient who developed non-cardiogenic pulmonary edema within a day after cutting copper pipe with an oxyethylene torch. The patient was a 26-year-old welder. He complained of dyspnea, generalized myalgia, and febrile sensation the following morning. The patient's chest X-ray and chest CT scan showed extensively distributed and ill-defined centrilobular nodules. Both his symptoms and chest X-ray abnormalities improved spontaneously. We attributed the patient's symptoms to non-cardiogenic pulmonary edema due to nitrogen dioxide, reasoning that: 1) the pipe consisted only of copper, according to material safety data sheet (MSDS); 2) a previous report in the literature demonstrated increased nitrogen dioxide levels under similar conditions; 3) the patient's clinical course and radiologic findings were very reminiscent of non-cardiogenic pulmonary edema following accidental exposure to nitrogen dioxide.

• Journal of the Korea Convergence Society
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• v.12 no.10
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• pp.129-136
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• 2021

Radiation shields used in medical institutions mainly use lead to manufacture products and fitments. Although lead has excellent processability and economic efficiency, its use is being reduced due to environmental issues when it is disposed of. In addition, when used for a long time, there is a limit to using it as a shielding film, shielding wall, medical device parts, etc. due to cracking and sagging due to gravity. To solve this problem, copper, tin, etc. are used, but tungsten is mostly used because there is a difficulty in the manufacturing process to control the shielding performance. However, it is difficult to compare with other shielding materials because the characteristics according to the type of tungsten are not well presented. Therefore, in this study, a medical radiation shielding sheet was manufactured in the same process using pure tungsten, tungsten carbide, and tungsten oxide, and the particle composition and shielding performance of the sheet cross-section were compared.As a result of comparison, it was found that the shielding performance was excellent in the order of pure tungsten, tungsten carbide, and tungsten oxide.

• Journal of radiological science and technology
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• v.24 no.1
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• pp.23-26
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• 2001

The spatial distribution of the scattered dose for mobile X-ray radiography is measured. The scattered X-ray exposures at the radius of 50, 100 and 150 cm from the irradiation center are 880, 180 and $50\;{\mu}R$, respectively. This scattered X-rays can be reduced to 60% by inserting the portable shield made by 0.4 mm copper sheet sandwiched in two plywoods.

• Proceedings of the KSME Conference
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• 2001.11a
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• pp.73-79
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• 2001

In this paper, shielding effectiveness(SE) of the shielding material of electromagnetic(EM) waves was investigated with actual experiments. The materials used in this study were made up of sputtering, film and powder of conductive materials - Cr, Al, Ag and Cu etc. Also, the polyester film was used as a base material. The experiment was carried out by using a shielding evaluator(Shielding box) TR17302 with an ADVANTEST spectrum analyzer, model R3361C. It was found from the experimental results that silver, copper, aluminum and chromium were good candidates as a shielding material against the EM waves with increasing the SE as the composite was laminated. The characteristics of the SE against the EM waves depended on a mode of preparation of specimen. The effects of density of particles on the SE were studied when the sputtering. The SE strongly depended on the electric resistance by density of sputtering and painting particles. SE increased as the density of particles was increasing.