• Journal of the Korean institute of surface engineering
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• v.29 no.5
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• pp.549-555
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• 1996

Diamond Like Carbon film is amorphous film which is considered to consist of three coordinate graphite structure and tetrahedron coordinate diamond structure. Its hardness, thermal conductivity and chemical stability are nearly to one of diamond. It is well known to become semi-conductor by doping of inpurity. In this study Diamond Like Carbon film was synthesized by Microwave Plasma CVD in the gas mixture of hydrogen-methan-nitrogen and doped of nitrogen on the single-crystal silicon or silica glass. The temperature of substrate and nitrogen concentration in the gas mixture had an effect on the bonding state, structural properties and conduction mechanism. The surface morphology was observed by Scanning Electron Microscope. The strucure was analyzed by laser Raman spectrometry. The bonding state was evaluated by electron spectroscopy. Diamond Like Carbon film synthesized was amorphous carbon containing the $sp^2$ and $sp^3$ carbon cluster. The number of $sp^2$ bonding increased as nitrogen concentration increased from 0 to 40 vol% in the feed gas at 1233K substrate temperature and at $7.4\times10^3$ Pa. Increase of nitrogen concentration made Diamond Like Carbon to be amorphous and the doze of nitragen could be controlled by nitrogen concentration of feed gas.

• Journal of Welding and Joining
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• v.27 no.5
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• pp.68-73
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• 2009

The bar horn is designed to increase uniformity of the displacement on the output face through simulation and experiments. Three-dimensional modal analysis is conducted using the finite element method to calculate the vibration mode and displacement on the output face, and the design of experiment (DOE) technique is employed to determine the optimum dimensions of the groove and slot so that the high amplitude uniformity of the bar horn is produced. Displacement of the bar horn was measured using the Laser Doppler Vibrometer (LDV), and the experimental results show good agreements with the predicted results. High uniformity of the bar horn is achieved with the dimensions of the groove and slot determined using the design equations.

• Applied Science and Convergence Technology
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• v.24 no.3
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• pp.60-66
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• 2015

The modified amorphous GeTe formed by pulsed laser irradiation in as-grown GeTe has been analyzed in terms of variations of local bonding structure using extended x-ray absorption fine structure (EXAFS). The modified GeTe film has octahedral-like Ge-Te bonding structure that can be effectively induced by irradiation process. The EXAFS data clearly shows that the irradiation can lead to reduction of the average coordination number. Variations in the transition temperature for the irradiated film during crystallization can be described by the presence of octahedral-like local structure.

• 제어로봇시스템학회:학술대회논문집
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• 2001.10a
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• pp.131.3-131
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• 2001

A 2-dimensional scanner have been generally used for an office, but 3-dimensional one was seldom used in industry. A footwear bonding process has been operated manually by the skilled operators, but it is needed to be operated automatically. So we developed an automatic outsole profile scanner, which consists of PC, CCD camera, laser beam diode and moving mechanism, to scan automatically the 3-dimensional profile of outsole inner face to be bonded. Here the developed algorithm makes 2D image into 3D outsole profile. This profile will be used enough to bond automatically the outsole to something like leather or clothes.

• 한국정보디스플레이학회:학술대회논문집
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• 2000.01a
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• pp.133-134
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• 2000

Effect of nitrogen doping on field emission characteristics of patterned Diamond-like Carbon (DLC) films was studied. The patterned DLC films were fabricated by the method reported previously[1]. Nitrogen doping in DLC film was carried out by introducing $N_2$ gas into the vacuum chamber during deposition. Higher emission current density of $0.3{\sim}0.4$ $mA/cm^2$ was observed for the films with 6 at % N than the undoped films but the emission current density decreased with further increase of N contents. Some changes in CN bonding characteristics with increasing N contents were observed. The CN bonding characteristics which seem to affect the electron emission properties of these films were studied by Raman spectroscopy, x-ray photoemission spectroscopy (XPS) and Fourier transform infrared spectroscopy (FT-IR). The electrical resistivity and the optical band gap measurements showed consistence with the above analyses.

• ETRI Journal
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• v.28 no.5
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• pp.648-651
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• 2006

In this letter we present a right-angle-bent coplanar waveguide (CPW) which we developed for the application of the driver amplifier-integrated (DAI) 40 Gbps traveling wave electroabsorption modulated laser module. The developed CPW realized parallel progression of the radio frequency (RF) and light using a dielectric overlay structure and wedge bonding on the bending section. The measured $S_{11}$ and $S_{21}$ of the developed CPW were kept below-10 dB up to 35 GHz and -3 dB up to 43 GHz, respectively. These measured results of the CPW were in good agreement with the simulation results and demonstrated the applicability of the CPW to the 40 Gbps communication module.

• Proceedings of the Polymer Society of Korea Conference
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• 2006.10a
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• pp.363-363
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• 2006

Bonding of composite materials with an adhesive layer is one of the most promising alternatives to classical bonding techniques. The use of several surface treatments may greatly increase this adhesion behavior at the initial state. Then in order to see the influence of the thickness of polymer matrix on the adhesion of composite assembly, different surface treatment, which can reduce or increase this thickness, are used (peel ply, tear ply, excimer laser). The influence of this specific parameter is not only discussed at the initial state but also after thermal ageing of the whole bonded assembly. Results show that the best performances at the initial state are not obviously the best performances after ageing.

• Journal of the Microelectronics and Packaging Society
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• v.30 no.2
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• pp.33-42
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• 2023

Throughout all industries, eco-friendliness is being promoted worldwide with focus on suppressing the environmental impact. With recent international environment policies and regulations supported by government, the electric vehicles demand is expected to increase rapidly. Battery system itself perform an essential role in EVs technology that is arranged in cells, modules, and packs, and each of them are connected mechanically and electrically. A multifaceted approach is necessary for battery pack bonding technologies. In this paper, pros and cons of applicable bonding technologies, such as resistance welding, laser and ultrasonic bonding used in constructing electric vehicle battery packs were compared. Each bonding technique has different advantages and limitations. Therefore, several criteria must be considered when determining which bonding technology is suitable for a battery cell. In particular, the shape and production scale of battery cells are seen as important factors in selecting a bonding method. While dealing with the types and components of battery cells, package bonding technologies and general issues, we will review suitable bonding technologies and suggest future directions.

• Restorative Dentistry and Endodontics
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• v.24 no.2
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• pp.310-321
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• 1999

In this in vitro study, confocal laser scanning microscopic morphology of dentin-resin interface and its relationship to shear bond strength were investigated after the exposed dentin surfaces were treated with 3 different kinds of dentin adhesive systems[three-step; Scotchbond Multi-Purpose Plus(SMPP), self-priming bonding resin; Single Bond(SB), self-etching primer; Clearfil Liner Bond 2(LB2)]. 52 extracted human molar teeth without caries and/or restorations. The experimental teeth were randomly divided into three groups of seventeen teeth each. In five teeth of each group, class V cavities(depth: 1.5mm) with 900 cavosurface angles were prepared at the cementoenamel junction on buccal and lingual surfaces. Bonding resins of each dentin adhesive system were mixed with rhodamine B. Primer of SMPP was mixed with fluorescein. In group 1. the exposed dentin was conditioned with etchant, applied with above primer and bonding resin of SMPP. In group 2, with etchant and self-priming bonding agent of SB. In group 3, with self-etching primer and bonding agent of LB2. After treatment with dentin adhesive systems, composite resin were applied and photocured. The experimental teeth were cut longitudinally through the center line of restoration and grounded so that about $90{\mu}m$-thick wafers of buccolingually orientated dentin were obtained. And, $70{\sim}80{\mu}m$-thick wafers sectioned horizontally, thus presenting a dentinal tubules at 900 to the cut surface of a remaining tooth, were obtained. Primer of SMPP mixed with rhodamine B was applied to these wafers. Confocal laser scanning microscopic investigations of these wafers were done within of 24 hours after treatment. To measure shear bond strength, the remaining twelve teeth of each group were grounded horizontally below the dentinoenamel junction, so that no enamel remained. After applying dentin adhesive systems on the dentin surface, composite was applied in the shape of cylinder. The cylinder was 5mm in diameter, and 2mm in thickness. Shear bond strength was measured using Instron with a cross-head speed of 0.5mm/min. It was concluded as follows ; 1. Hybrid layer of SMPP(mean: $4.56{\mu}m$) was thicker than that of any other groups. This value was not statistically significant thicker than that of SB(mean: $3.41{\mu}m$, p>0.05), and significant thicker than that of LB2(mean: $1.56{\mu}m$, p<0.05). There was a statistical difference between SB and LB2(p<0.05). 2. Although there were variations in the length of resin tag even in a sample, and in a group, most samples in SMPP and SB showed resin tags extending above $20{\mu}m$. But samples in LB2 showed resin tags of $10{\mu}m$ at best. 3. Besides primer's infiltration into demineralized peritubular dentin and dentinal tubules, fluorophore of primer was detected in the lateral branches of dentinal tubules. 4. All groups demonstrated statistically significant differences from one another(p<0.05), with shear bond strengths given in descending order as follows: SMPP(18.3MPa), SB(16.0MPa) and LB2(12.4MPa). 5. LB2 having thinnest hybrid layer($1.56{\mu}m$) showed the lowest shear bond strength(12.4MPa).

• Journal of Advanced Marine Engineering and Technology
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• v.37 no.2
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• pp.144-148
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• 2013

In this paper, the ultra water-repellent thin films were prepared by RF PECVD. On the basis of surface morphology, chemical bonding states and plasma diagnostics, a formation model of clusters for the ultra water-repellent films was discussed from considerations of formation process and laser scattering results. Moreover, using laser scattering method, the relative change of quantity of nano-clusters or size of agglomerates could be confirmed. From the results, the films were deposited with nano-clusters and those of agglomerates, which formed in organosilicon plasma, and formation of agglomerates were depended on the deposition time.