• Proceedings of the Korean Vacuum Society Conference
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• 2010.08a
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• pp.79-79
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• 2010

The electronic and adsorption structure of O-Phthaladehyde (OPA) on the H-Si(100) surface was investigated by using Near Edge X-ray Fine Structure (NEXAFS) and high resolution photoemission spectroscopy (HRPES). We confirmed that the OPA grown on the H-Si(100) surface showed good dependency with about 60 degree tilting angle using NEXAFS and a single O 1s peak by using HRPES. Hydrogen atom passivated on the Si(100) surface was found to be a seed for making one dimensional organic line that uses a chain reaction as the H-Si(100) surface was compared with the hydrogen free Si(100) surface. Through the spectral analysis, we will demonstrate 1-D directional formation of OPA on H-Si(100) surface using NEXAFS and HRPES.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.13 no.10
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• pp.817-821
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• 2000

In this work, we have investigated the dependence of annealing temperature(T$\_$a/) on optical and electrical properties of amorphous hydrogenated SiC(a-SiC:H) films. The a-SiC:H films were deposited on corning glass and p-type Si(100) wafer by PECVD (plasma enhanced vapor deposition) using SiH$_4$+CH$_4$+N$_2$ gas mixture. The experimental results have shown that the optical energy band gap(E$\_$opt/)of the thin films annealed at high temperatures have shown that the graphitization of carbon clusters and micro-crystalline silicon occurs. The current-voltage characteristics have shown good electrical properties at the annealed films.

• Journal of the Korean institute of surface engineering
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• v.48 no.3
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• pp.126-130
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• 2015

A high-pressure depletion method using plasma chemical vapor deposition (CVD) is often used to deposit hydrogenated microcrystalline silicon (${\mu}c-Si:H$) films of a low defect density at a high deposition rate. To understand proper deposition conditions of ${\mu}c-Si:H$ films for a high-pressure depletion method, Si films were deposited in a combinatorial way using a multi-hollow discharge plasma CVD method. In this paper the substrate temperature dependence of ${\mu}c-Si:H$ film properties are demonstrated. The higher substrate temperature brings about the higher deposition rate, and the process window of device quality ${\mu}c-Si:H$ films becomes wider until $200^{\circ}C$. This is attributed to competitive reactions between Si etching by H atoms and Si deposition.

• Journal of the Korean institute of surface engineering
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• v.23 no.3
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• pp.160-166
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• 1990

The effects of the variation of proedd varibles on the flow patterns and effects of the flow patterns on the deposition rate and uniformity in the Si-epitaxy CVD with SiH4 as the source of Si were studied through the calculation by use of control volume method. The reslts showed that the natural convection was undesirable to the uniformity of deposition rate, whose effects were decreased with the dercrese with the decrese of the pressure in the reactoor and with the increase of the flow rate. However. the excessive increase of flow rate caused the movement of the unreacted gas to the substrate. Therefore it resulted in the non-uniform depositions. The rotation of substrate was apperared to improve the uniformity. The resulte of this study could used in CVD process to design the reator and to find the optimum conditions of the process variables.

• Journal of the Korean Vacuum Society
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• v.17 no.6
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• pp.528-537
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• 2008

60 nm and 20 nm thick hydrogenated amorphous silicon(a-Si:H) layers were deposited on 200 nm $SiO_2$/single-Si substrates by inductively coupled plasma chemical vapor deposition(ICP-CVD). Subsequently, 30 nm-Ni layers were deposited by an e-beam evaporator. Finally, 30 nm-Ni/(60 nm and 20 nm) a-Si:H/200 nm-$SiO_2$/single-Si structures were prepared. The prepared samples were annealed by rapid thermal annealing(RTA) from $200^{\circ}C$ to $500^{\circ}C$ in $50^{\circ}C$ increments for 40 sec. A four-point tester, high resolution X-ray diffraction(HRXRD), field emission scanning electron microscopy(FE-SEM), transmission electron microscopy(TEM), and scanning probe microscopy(SPM) were used to examine the sheet resistance, phase transformation, in-plane microstructure, cross-sectional microstructure, and surface roughness, respectively. The nickel silicide from the 60 nm a-Si:H substrate showed low sheet resistance from $400^{\circ}C$ which is compatible for low temperature processing. The nickel silicide from 20 nm a-Si:H substrate showed low resistance from $300^{\circ}C$. Through HRXRD analysis, the phase transformation occurred with silicidation temperature without a-Si:H layer thickness dependence. With the result of FE-SEM and TEM, the nickel silicides from 60 nm a-Si:H substrate showed the microstructure of 60 nm-thick silicide layers with the residual silicon regime, while the ones from 20 nm a-Si:H formed 20 nm-thick uniform silicide layers. In case of SPM, the RMS value of nickel silicide layers increased as the silicidation temperature increased. Especially, the nickel silicide from 20 nm a-Si:H substrate showed the lowest RMS value of 0.75 at $300^{\circ}C$.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.8 no.1
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• pp.29-35
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• 1998

Substrates, SiC raw materials and graphite crucibles were purified for growing the high quality 6H-SiC single crystal ingot. Especially, XRD data of raw materials were analyzed before and after purification. We have grown 6H-SiC single crystal ingot up to 33 mm in diameter and 11 mm in length and SiC wafer for using the substrate and observing the internal defects was about 33 mm in diameter and 0.5 mm in thickness. Utilizing optical microscpe and Raman spectroscopy, internal defects density and crystallinity of the SiC wafer obtained by purification processes before crystal growth were measured. As a result, micropipe density and planar defect density were 100/$\textrm{cm}^2$ and 30/$\textrm{cm}^2$ respectively. Therefore, high quality 6H-SiC single crystal could be grown because internal defects density of 6H-SiC single crystal ingot was decreased by the purification processes before crystal growth.

• Proceedings of the KIEE Conference
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• 2003.07c
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• pp.1592-1594
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• 2003

This paper presents the deposition and characterization of microcrystalline silicon(${\mu}c$-Si:H) films by HWCVD(Hot-wire Chemical Vapor Deposition) method at low substrate($300^{\circ}C$). The filament temperature, pressure and $SiH_4$ concentration were determined to be a critical parameter for the deposition of poly-Si films. Series A was deposited under the conditions of $1380^{\circ}C$(Tf), 100 mTorr and $2{\sim}10%\{SC:SiH_4/(SiH_4+H_2)\}$ for 60 min. Series B was deposited under the conditions of $1400{\sim}1450^{\circ}(T_f)$, 30 mTorr and $2{\sim}12%$(SC) for 60 min. The physical characteristics were measured by Raman and FTIR spectroscopy, dark and photoconductivity measurements under AM1.5 illumination.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.05b
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• pp.54-56
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• 2001

The $SiH_4$ soak step is widely used during the CVD Tungsten(W) plug deposition process on the Ti/TiN barrier metal to prevent the $WF_6$ attack to the underlayer metal. We tried to reduce or skip the time of $SiH_4$ soak process to optimize W-plug deposition process on Via. The electrical characteristics including Via resistance and the structure of W film are affected according to $SiH_4$ soak time. The elimination possibility of $SiH_4$ soak process was confirmed in the case of that the CVD W film grows on the stable Ti/TiN underlayer.

• 한국정보디스플레이학회:학술대회논문집
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• 2005.07b
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• pp.940-943
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• 2005

The characteristics of a-Si:H TFTs with silicon oxide as passivation layer were reported. It was studied that the insulating characteristics and step coverage characteristics of low temperature silicon oxide before applying to a-Si:H TFT fabrications. With the optimum deposition conditions considering electrical and deposition characteristics, low temperature silicon oxide was applied to a-Si:H TFTs. The changes in characteristics of a-Si:H TFTs were analyzed after replacing silicon nitride passivation layer with low temperature silicon oxide layer. This low temperature silicon oxide can be adapted to high resolution a-Si:H TFT LCD panels.

• Proceedings of the KIEE Conference
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• 1998.07d
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• pp.1288-1290
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• 1998

Three most dominant reactions are adsorption, movement, and desorption of $SiCl_2$ on silicon surface. $SiCl_2$ plays a key role in these dominant reactions. In this paper, surface reactions of $SiH_2Cl_2-H_2-HCl$ system are investigated and few dominant reactions were identified. An equation for Si net growth rate is derived from the analysis of these reactions and it is compared with experimental results of Bolem and Classen.