• The Transactions of The Korean Institute of Electrical Engineers
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• v.66 no.2
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• pp.370-378
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• 2017

A fluid model of 2D axis-symmetry based on inductively coupled plasma (ICP) reactor using $N_2/NH_3/SiH_4$ gas mixture has been developed for hydrogenated silicon nitride ($SiN_x:H$) deposition. The model was comprised of 62 species (electron, neutral, ions, and excitation species), 218 chemical reactions, and 45 surface reactions. The pressure (10~40 mTorr) and gas mixture ratio ($N_2$ 80~96 %, $NH_3$ 2~10 %, $SiH_4$ 2~10 %) were considered simulation variables and the input power fixed at 1000 W. Different distributions of electron, ions, and molecules density were observed with pressure. Although ionization rate of $SiH_2{^+}$ is higher than $SiH_3{^+}$ by electron direct reaction with $SiH_4$, the number density of $SiH_3{^+}$ is higher than $SiH_2{^+}$ in over 30 mTorr. Also, number density of $NH^+$ and $NH_4{^+}$ dramatically increased by pressure increase because these species are dominantly generated by gas phase reactions. The change of gas mixture ratio not affected electron density and temperature. With $NH_3$ and $SiH_4$ gases ratio increased, $SiH_x$ and $NH_x$ (except $NH^+$ and $NH_4{^+}$) ions and molecules are linearly increased. Number density of amino-silane molecules ($SiH_x(NH_2)_y$) were detected higher in conditions of high $SiH_x$ and $NH_x$ molecules density.

• Journal of Soil and Groundwater Environment
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• v.22 no.6
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• pp.22-28
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• 2017

The accuracy of analytical results in response to the use of different additives ($NH_4Cl$, KCl, $LaCl_3$) and oxidant gases was evaluated and compared by using Atomic Absorption Spectrometry (AAS). Identification of spectroscopic interferences and possible improvements in Inductively Coupled Plasma-Atomic Emission Spectrometry (ICP-AES) analysis were also discussed. The average accuracies of total chromium using Certified Reference Materials (CRMs) were found to be 72.1~94.2% in air/acetylene flame condition by AAS, and they were improved to 100.5~110.5% when the oxidants was changed to nitrous oxide rather than adding the additives. The field samples showed similar trends to CRMs, but chromium concentrations were highly variable depending on analytical conditions. The average accuracies using CRMs were estimated to be 89.3~166.1% by ICP-AES, and improved to below 121.7% after eliminating iron interference. Field samples with low chromium and high iron concentration were measured to be > 30% lower in total chromium concentrations by ICP-AES than AAS in nitrous oxide/acetylene flame. Total chromium concentrations in soil could be analyzed with better accuracy under nitrous oxide/acetylene flame by AAS because it was more effective to increase the temperature of the flame than to eliminate the chemical interference for maximizing atomization of chromium. When using ICP-AES, interference substances, total chromium levels, and analytical conditions should be also considered.

• Corrosion Science and Technology
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• v.4 no.6
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• pp.226-230
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• 2005

Si incorporated diamond-like carbon (Si-DLC) films ranging from 0 to 2 at.% contents were deposited on STS 316L substrates for orthopedic implants by means of r.f. plasma-assisted chemical vapor deposition (r.f. PACVD) technique, using mixtures of benzene ($C_6H_6$) and silane ($SiH_4$) as the precursor gases. This study provides the reliable and quantitative data for assessment of the effect of Si incorporation on corrosion property in the simulated body fluid environment through the electrochemical test. It was found that corrosion to resistance of Si-DLC coatings with increasing Si content are improved owing to high $sp^3$ bonding.

• Korean Journal of Materials Research
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• v.13 no.3
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• pp.150-154
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• 2003

Amorphous carbon nitride films were deposited on Si(001) substrates by a plasma enhanced chemical vapor deposition technique (PECVD) using $CH_4$and $N_2$as reaction gases. The growth and film properties were investigated while the gas ratio and the working pressure were changed systematically. At 1 Torr working pressure, an increase in the $N_2$partial pressure results in a significant increase of the deposition rate as well as an apparent presence of C ≡N bonding, while little affecting the microstructure and amorphus nature of the films. In the case of changing the working pressure at a fixed $N_2$partial pressure of 98%, a film grown at a medium pressure of $1${\times}$10^{-2}$ Torr shows the most prominent C=N bonding nature and photoluminescent property.

• Proceedings of the International Microelectronics And Packaging Society Conference
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• 2001.07a
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• pp.110-113
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• 2001

ECR(electron cyclotron resonance) 플라즈마 식각 장비를 이용하여 SF$_{6}$/Ar과 Cl$_2$/Ar 플라즈마 가스에 대한 Platinum (이하 Pt) 박막의 식각 특성을 연구하였다. Pt 박막의 경우 Cl$_2$ 가스 혼합물에 대한 식각 특성은 많이 보고가 되어 왔으나 상대적으로 Fluorine 계열의 가스 혼합물에 의한 시각 연구는 미비하였다. 본 연구에서는 SF$_{6}$/Ar과 Cl$_2$/Ar 플라즈마 가스를 이용한 Pt 박막의 식각 특성을 비교 분석하고 각각의 가스와 Pt 박막과의 반응을 분석, 식각 특성을 개선하고자 하였다.

• 한국정보디스플레이학회:학술대회논문집
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• 2004.08a
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• pp.495-498
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• 2004

PDP use the mixture of inert gases to generate a discharge inside display pixels. Inside of PDP, there exist highly reactive conditions in the gap between two glass panels. MgO layer and phosphor have been investigated as a function of discharge and thermal process. Impurities such as CO, $CO_2$, OH and $H_2O$ in discharge region may deteriorate the characteristics of PDP operation during life time. Change of impurity generation of various MgO and phosphor surfaces were measured by using x-ray photoelectron spectroscopy(XPS) and quadropole mass spectrometer (QMS). Carbon containing species such as C, CO and $CO_2$ were drastically increased on the surfaces during discharge and thermal treatment. Carbon impurities on the MgO and phosphor are the dominant factor for their instability.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.54 no.9
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• pp.421-426
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• 2005

A wire-plate discharge system with a slit barrier has been proposed and investigated experimentally by focusing on the discharges on the slit barrier and ozone generation characteristics. This wire-plate discharge system with a slit barrier can generate an intensive corona discharges, and produce corona discharge twice, once from the corona wire electrode and second time from the surface and the slits of the slit dielectric barrier. As a result this propose wire-plate discharge system with the slit barrier can produce greatly increased ozone than without the slit barrier. This type of wire-plate discharge system with the slit barrier could be used for effective ozone generation as a means with retard to the removal of pollutant gas

• Journal of the Korean Vacuum Society
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• v.4 no.1
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• pp.12-17
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• 1995

Diamondlike carbon(DLC)films having good characteristics in mechanical and optical properties, were synthesized by rf-plasma enhanced chemical vapor deposition method. Methane, methane-hydrogen, or methane-argon were used as source gases. The infrared transparency and composition of the films were investigate. Especially, the anti-reflection effect of KLC film in infrared region was confirmed by depositing it on Ge/Si sample. When DLC films were deposited on the plastic substrates and thermal distortion, which were originated before and during deposition, respectively, played a role as a crack source of the films.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.22 no.7
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• pp.612-615
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• 2009

We need to control the growth orientation of CNTs on a substrate for applications to various electric devices. Generally, the flow direction of feed gases and electric field between two electrode affect to growth orientations of CNTs. In this paper, we varied tilt degrees $(0^{\circ},\;20^{\circ},\;35^{\circ},\;50^{\circ},\;65^{\circ},\;90^{\circ})$ of substrates on a cathode and DC bias voltages (0, 500, 700 V) applied between two electrodes in order to change growth orientations of CNTs. We confirmed that tilt degrees of the substrate and variation of DC bias voltages affected to the shape and orientation of the grown CNTs on the substrate.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.07a
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• pp.499-502
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• 2001

In this experiment, an attempt to use the sludge pellets as catalyst for NO removal from simulated gas is experimentally investigated by using cylinder type reactor and packed-bed reactor. An experimental investigation has been conducted for NO concentration of 50[ppm], 100[ppm], 200[ppm] balanced with air, a gas flow rate of 5[1/min]. Ac voltage to discharge the gases was supplied. In the result, NOx removal rate in packed bed reactor is higher than that in cylinder type reactor. it is thought that plasma density in contact point of BaTiO$_3$ is significantly higher than that in cylinder reactor.