• 전기의세계
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• 제27권4호
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• pp.45-51
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• 1978

A new method of realizing the field effect transistor with a sub-.mu. channel width is described. The sub-.mu. channel width is made possible by etching grooves into n$^{+}$ pn$^{[-10]}$ n$^{[-10]}$ structure and using p region at the wall for the channel region of the Metal-Oxide-Semiconductor transistor (MOST), or by diffusing two different types of impurities through the same diffusion mask and using p region at the surface for the channel region of MOST. When the drain voltage is increased at the pn$^{[-10]}$ drainjunction the depletion layer extends into the n$^{[-10]}$ region instead of into p region; this is also the secret of success to realize the sub-.mu. channel width. As the result of the experimental fabrication, a microwave MOST was obtained. The cut-off frequency was calculated to be 15.4 GHz by Linvill's power equation using the measured capacitances and transconductance.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1992년도 하계학술대회 논문집 B
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• pp.813-815
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• 1992

Accurate Capacitance-Voltage characteristics of Metal-Insulator-Semiconductor (MIS) devices in narrow band-gap semiconductors are presented. The unique band structure of narrow band-gap semiconductors is taken into account such as non-parabolicity and degeneracy. Compensated and partially ionized impurities either in the bulk or the space charge region are also considered. HgCdTe is a defect semiconductor, so this approach is very important for characterization and analysis of MIS devices.

• 분석과학
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• 제11권4호
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• pp.311-315
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• 1998

Ultra trace metal impurities of high-purity sulfuric acid for semiconductor process have been determined in the concentration of lower than ppb (ng/g) level using high resolution inductively coupled plasma mass spectrometer (HR-ICP-MS).The acid samples were evaporated and concentrated by the factor of 20. No clement in the acids exceeded 1ppb level and most of the clements were determined below 10ppt (pg/g). Elements without spectral interference in mass spectrum, such as In, V, Mn, etc, were determined in the concentration of below 1 ppt level The recoveries in the range of 72% to 127.2% for 0.5 ppb spiked sample were obtained.

• 대한전자공학회논문지
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• 제27권5호
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• pp.724-728
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• 1990

The X-ray diffraction pattern, electrical resistance, density and critical temperature of a series of YBa2(Cu3-xNix)O7-\ulcornersamples (0\ulcorner\ulcorner.5) were investigated with the increase of the Ni content. The samples show a principal 1.2.3-like phase with well resolved orthorhombic peaks. The final pattern of the x=0.1 sample appears to be well reacted orthorhombic YBa2(Cu,Ni)3O7-\ulcornerwith minor impurities and an appreciable amorphous fraction. From the above results, we conclude that Ni does not play an important role for the superconductivity in the Y-Ba-Cu-O system.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1998년도 하계학술대회 논문집 D
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• pp.1327-1329
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• 1998

It is very important to select superior inter-layer PMD(Pre Metal Dielectric) materials which can act as penetration barrier to various impurities created by CMP processes. In this paper, hot carrier degradation and device characteristics were studied with material variation of PMD-1 layers, which were split by LP-TEOS, SR-Oxide, PE-Oxynitride, PE-Nitride, PE-TEOS films. It was observed that the oxynitride and nitride using plasma was greatly decreased in hot carrier effect in comparison with silicon oxide. Consequently, silicon oxide turned out to be a better PMD-1 material than PE-oxynitride and PE-nitride. Also, LP-TEOS film was the best PMD-1 material Among the silicon oxides.

• Carbon letters
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• 제14권3호
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• pp.152-161
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• 2013

Needle coke is an important material for graphite electrodes. Delayed coking is used to produce needle coke. Producing good quality needle coke is not simple because it is a multi-parameter controlled process. Apart from that, it is important to understand the mechanism responsible for the delayed coking process, which involves mesophase formation and uniaxial rearrangement. Temperature and pressure need to be optimized for the different substances in every feedstock. Saturate hydrocarbon, aromatic, resin and asphaltene compounds are the main components in the delayed coking process for a low Coefficient Thermal Expansion value. In addition, heteroatoms, such as sulphur, oxygen, nitrogen and metal impurities, must be considered for a better graphitization process that prevents the puffing effect and produces better mesophase formation.

• 한국세라믹학회지
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• 제48권2호
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• pp.189-194
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• 2011

Metallurgical grade silicon was recovered from slurry waste for ingot sawing process by acid leaching and thermal treatment. SiC abrasive was removed by gravity concentration and centrifugation. Metal impurities were removed by the acid leaching using HF/HCl. The remaining SiC was separated by the thermal treatment at $1600^{\circ}C$ in an inert atmosphere by the difference in melting points. The purity of the obtained silicon was found to be around 99.7%.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2005년도 추계학술대회 논문집 Vol.18
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• pp.72-73
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• 2005

Stress behavior was studied to investigate the internal behaviors of boron, carbon, and nitrogen in the 1000${\AA}$-thick tungsten boron carbon nitride (W-B-C-N) thin films. The impurities in the W-B-C-N thin films provide stuffing effects that were very effective for preventing the interdiffusion between interconnection metal and silicon substrate during the subsequent high temperature annealing process. The resistivity of W-B-C-N thin film decreases as an annealing temperature increase. The W-B-C-N thin films have compressive stress, and the stress value decreased up to $4.11\times10^{10}dyne/cm^2$ as an $N_2$ flow rate increases up to 3 sccm.

• 한국표면공학회지
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• 제29권6호
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• pp.851-856
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• 1996

Copper Phthalocyanine (CuPc) thin films were fabricated on the silicon wafers by plasma activated evaporation method and structural analysis were carried out with various spectroscopies. The CuPc films had dense and smooth morphology and they also showed good mechanical properties and chemical resistance. The main molecular structure of the CuPc, which is the conjugated aromatic heterocyclic ring structure, was maintained even in the plasma process. However, metal-ligand (Cu-N) bands were deformed by the plasma process and the structure became amorphous especially at higher process pressures. Oxygen impurities were incorporated in the film and carboxyl functional groups were formed at the peripheral benzene ring. The structure and morphology of the films were dependent on the process pressure but relatively irrespective of the RF power.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1997년도 하계학술대회 논문집 C
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• pp.1196-1198
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• 1997

In this work, simultaneous measurement such as change distribution and electrical conduction of maleic anhydride grafted XLPE was investigated. Heterocharge was found in XLPE and it decreased with increasing MAR graft ratio in XLPE-g-MAH. Conduction currents also decreased with increasing MAR graft ratio. The relationship between the space change behavior and the electrical conduction characteristics in XLPE-g-MAH is discussed.