• 대한전기학회:학술대회논문집
• /
• 대한전기학회 1998년도 하계학술대회 논문집 D
• /
• pp.1525-1527
• /
• 1998

The line-fuse which one of device most widely used in distributed line system has a ability to cut off the fault current flow into the house. But this device can be used only one time. So there are many waste of human power and money to exchange acted line-fuse. In this paper, we designed new type of line-fuse melting zone using by different union metal, so line-fuse can be reused after once operated.

• 소성∙가공
• /
• 제28권2호
• /
• pp.83-88
• /
• 2019

This paper introduces a new concept - on-line FE model, as applied to metal rolling. The new technology allows for completion of process simulation within a tiny fraction of a second without loss of high-level prediction accuracy inherent to FEM. The three steps of an on-line FE model design namely, process metamorphosis, mesh design, and process variable design, are described in detail. The procedure is demonstrated step by step through designing actual on-line models for the prediction of the dog-bone profile in edge rolling. The validity and prediction accuracy of the on-line FE models are analyzed and discussed.

• 한국정밀공학회:학술대회논문집
• /
• 한국정밀공학회 2002년도 춘계학술대회 논문집
• /
• pp.104-107
• /
• 2002

Direct Metal Manufacturing (DMM) is a new additive process that aims to take die making and metalworking in an entirely new direction. It is the blending of five common technologies : lasers, computer-aided design (CAD), computer-aided manufacturing (CAM), sensors and powder metallurgy. The resulting process creates parts by focusing an industrial laser beam onto a tool-steel work piece or platform to create a molten pool of metal. A small stream of powdered tool-steel metal is then injected into the melt pool to increase the size of the molten pool. By moving the laser beam back and forth, under CNC control, and tracing out a pattern determined by a computerized CAD design, the solid metal part is built line-by-line, one layer at a time. DMM produces improved material properties in less time and at a lower cast than is possible with traditional fabrication.

• 반도체디스플레이기술학회지
• /
• 제22권2호
• /
• pp.30-34
• /
• 2023

Since dishing in the CMP process is a major factor that hinders the uniformity of the semiconductor thin film, many studies have focused this issue to improve the non-uniformity of the film due to dishing. In the metal layer, the dishing mainly occurs in the central part of the metal due to a difference in a selection ratio between the metal and the dielectric, thereby generating a step on the surface of the metal layer. Factors that cause dishing include the shape of the thin film, the chemical reaction of the slurry, thermal deformation, and the rotational speed of the pad and head, and dishing occurs due to complex interactions between them. This study analyzed the stress generated on the metal layer surface in the CMP process using ANSYS software, a commercial structure analysis program. The stress caused by the vertical load applied from the pad was analyzed by changing the area density and line width of the dummy metal. As a result of the analysis, the stress in the active region decreased as the pattern density and line width of the dummy metal increased, and it was verified that it was valid compared with the previous study that studied the dishing according to the dummy pattern density and line width of the metal layer. In conclusion, it was confirmed that there is a relationship between dishing and normal stress.

• 한국전기전자재료학회:학술대회논문집
• /
• 한국전기전자재료학회 2007년도 하계학술대회 논문집 Vol.8
• /
• pp.545-545
• /
• 2007

Recently, innovative process has been investigated in order to replace the conventional high-cost micro patterning processes on the electronic products. To produce desirable profit margins from this low cost products, printed circuit board(PCB), will require dramatic changes in the current manufacturing philosophies and processes. Innovative process using metal nano particles replaces the current industry standard of subtractive etched of copper as a highly efficient way to produce robust circuitry on low cost substrates. An advantage of using metal nano particles process in patterned conductive line manufacturing is that the process is additive. Material is only deposited in desired locations, thereby reducing the amount of chemical and material waste. Simply, it just draws on the substrate as glass epoxy or polyimide with metal nano particles. Particles, when their size becomes nano-meter scale, show some specific characteristics such as enhanced reactivity of surface atoms, decrease in melting point, high electric conductivity compared with the bulk. Melting temperature of metal gets low, the metal nano particles could be formated onto polymer substrates and sintered under $300^{\circ}C$, which would be applied in PCB. It can be getting the metal line of excellent electric conductivity.

• Journal of Advanced Marine Engineering and Technology
• /
• 제32권8호
• /
• pp.1248-1256
• /
• 2008

In this paper, basic characteristics of transmission line employing PPGM (periodically perforated ground metal) were investigated using theoretical and experimental analysis.According to the results, unlike the conventional PBG (photonic band gap) structures, the characteristic impedance of the transmission line employing PPGM structure showed a real value, which exhibited a very small dependency on frequency. The transmission line employing PPGM structure showed a loss (per quarter wave length) higher by $0.1{\sim}0.2\;dB$ than the conventional microstrip line. According to the investigation of the dependency of RF characteristic on ground condition, the RF characteristic of the transmission line employing PPGM structure was hardly affected by the ground condition in the frequency lower than Ku band, but fairly affected in the frequency higher than Ku band, which indicated that coplanar waveguide employing PPGM structure was optimal for RF characteristic and reduction of size. Considering above results, impedance transformer was developed using coplanar waveguide with PPGM structure for the first time, and good RF characteristics were observed from the impedance transformer. In case that {\lambda}/4$ impedance transformer with a center frequency of 9 GHz was fabricated for a impedance transformation from 20 to10 {\Omega}$, the line width and length were 20 and $500\;{\mu}m$, respectively, and its size was only 0.64 % of the impedance transformer fabricated with conventional microstrip lines. Above results indicate that the transmission line employing PPGM is a promising candidate for a development of matching and passive elements on MMIC.

• JSTS:Journal of Semiconductor Technology and Science
• /
• 제1권1호
• /
• pp.20-30
• /
• 2001

A 1.8V $650{\;}\textrm{mm}^2$ 4Gb DRAM having $0.10{\;}\mu\textrm{m}^2$ cell size has been successfully developed using 0.11 $\mu\textrm{m}$DRAM technology. Considering manufactur-ability, we have focused on developing patterning technology using KrF lithography that makes $0.11{\;}\mu\textrm{m}$ DRAM technology possible. Furthermore, we developed novel DRAM technologies, which will have strong influence on the future DRAM integration. These are novel oxide gap-filling, W-bit line with stud contact for borderless metal contact, line-type storage node self-aligned contact (SAC), mechanically stable metal-insulator-silicon (MIS) capacitor and CVD Al process for metal inter-connections. In addition, 80 nm array transistor and sub-80 nm memory cell contact are also developed for high functional yield as well as chip performance. Many issues which large sized chip often faces are solved by novel design approaches such as skew minimizing technique, gain control pre-sensing scheme and bit line calibration scheme.

• 한국전자파학회:학술대회논문집
• /
• 한국전자파학회 2005년도 종합학술발표회 논문집 Vol.15 No.1
• /
• pp.273-278
• /
• 2005

The characteristics of the tag antenna are influenced much with the change of the electrical properties of its substrate material, conducting metal-line and the surrounding environments. In this paper, we study the characteristics of tag antenna according to the electrical variations of those substrate materials, metal-line and the surrounding environmental conditions.

• International Journal of Precision Engineering and Manufacturing
• /
• 제7권3호
• /
• pp.30-34
• /
• 2006

We investigated fatigue crack growth behavior in laser-welded sheet metal caused by a single applied overload The fatigue specimens were made using butt jointed cold rolled sheet metal that was welded with a $CO_2$ laser, The effects of the specimen thickness and overload ratio were determined from fatigue crack propagation tests, These tests were performed in such a way that the fatigue loading was aligned parallel to the weld line while the crack propagated perpendicular to the weld line, Overload ratios of 1.0, 1.5, and 2. 0 were applied near the tip of the fatigue crack at points located 6, 4, and 2 mm from the weld line. The specimens were either 0.9 or 2.0 mm thick. The size of the plastic zone at the crack tip due to the single applied overload was also determined using finite element analysis.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 2015년도 제46회 하계학술대회
• /
• pp.1155-1156
• /
• 2015

This study demonstrates hybrid-type transparent electrodes for touch screen panels. The hybrid-type electrodes were fabricated by coating carbon nanotubes (CNTs) on metal meshes. For the formation of metal meshes, thin films of silver (Ag) were deposited on glass substrates using a sputtering method and then pattenrned via photolithography to obtain mesh structures of which line width was $10{\mu}m$ and line-to-line spacing was $300{\mu}m$. CNTs were coated on Ag meshes by using electrophoretic deposition (EPD). For the samples of Ag meshes with/without CNTs, their surface morphologies, visible-range transmittances, and reflectances were characterized and compared. The experimental results indicated that the reflectance of Ag mesh electrodes was substantially reduced by coating of CNTs. Especially, the hybrid electrodes of Ag meshes with EPD-coated CNTs showed excellent properties such as transmittance higher than 90%, reflectance lower than 8%.