• Communications of the Korean Mathematical Society
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• v.17 no.3
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• pp.439-449
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• 2002

If an arrangement admits a nice partition, or an arrangement is free, then the characteristic polynomial of the arrangement can be factored. It is known that a free arrangement does not always admit a nice partition. We show that even an inductively free arrangement does not always admit a nice partition.

• Progress in Superconductivity and Cryogenics
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• v.11 no.1
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• pp.25-29
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• 2009

To reduce the power loss in normal state, non-inductively wound high temperature superconducting (HTS) coils are used for fault current limiter (FCL) application. Non-inductively wound coils can be classified into two types: solenoid type and pancake type. These two types have different electrical and thermal and mechanical characteristics due to their winding structure difference. This paper deals with the current limiting characteristics, magnetic field analysis of the two coils. Simulation using finite element method (FEM) was used to analyze the magnetic field distribution and inductance of the coils. Short circuit test using stabilizer-free coated conductor (CC) was also carried out. We can compare the characteristics of the two types of coil by using the data obtained from simulation and short circuit test. We confirmed the feasibility of FCL application by the analysis about the characteristics of non-inductively wound coil using CC.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2006.12a
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• pp.43-47
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• 2006

In this paper, parameters of electron temperature and density for the mercury-free lighting-source were measured to diagnosis and analyze in Xe based inductively coupled plasma (ICP). As results at several dependences of 20~100mTorr Xenon pressure, the brightness of discharge tube was higher (4,900 $cd/m^2$) than other conditions when Xe pressure was 20mTorr and RF power was 200W. In that case, the electron temperature and density were 3.58eV and $3.56{\times}10^{12}cm^2$, respectively. The key parameters of Xe based ICP depended on Xe pressure more than RF power that could be verified. A high electron temperature and low electron density with a suitable Xe pressure are indispensible parameters for Xe based ICP lighting-source.

• Journal of the Korean Vacuum Society
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• v.8 no.4A
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• pp.476-481
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• 1999

Characteristics of platinum dry etching were investigated in a cryogenic magnetized inductively coupled plasma (MICP). The problem with platinum etching is the redeposition of sputtered platinum on the sidewall. Because of the redeposits on the sidewall, the etching of patterned platinum structure produces feature sizes that exceed the original dimension of the PR size and the etch profile has needle-like shape [1]. The main object of this study was to investigate a new process technology for fence-free Pt etching As bias voltage increased, the height of fence was reduced. In cryogenic etching, the height of fence was reduced to 20% at-$190^{\circ}C$ compared with that of room temperature, however the etch profile was not still fence-free. In Ar/$SF_6$ Plasma, fence-free Pt etching was possible. As the ratio of $SF_6$ gas flow is more than 14% of total gas flow, the etch profile had no fence. Chemical reaction seemed to take place in the etch process.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2005.05b
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• pp.41-45
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• 2005

In this paper, parameters of electron temperature and density for the mercury-free lighting-source were measured to diagnosis and analyze in Xe based inductively coupled plasma(ICP). In results at several dependences of 20~100 mTorr Xenon pressure, 50~200W RF power and horizontal distribution were especially mentioned. When Xe pressure was 20mTorr and RF power was 200W, the electron temperature and density were respectively 3.58eV and $3.56{\times}10^{12}cm^{-3}$. The key parameters of Xe based ICP depended on Xe pressure more than RF power that could be verified. A high electron temperature and low electron density with a suitable Xe pressure are indispensible parameters for Xe based ICP lighting-source.

• Journal of the Korean Chemical Society
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• v.29 no.4
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• pp.382-389
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• 1985

The effect of plasma operational parameters for the determination of rare earth elements(REE) by means of inductively coupled plasma(ICP) spectrometry was investigated. While the increase in the flow rate of carrier gas argon enhanced the sensitivity and lowered the detection limit, significant ionization interferences were observed. The decrease in RF power increased the signal to background ratio. The observation point showing the lowest ionization interference was slightly higher than the position where the spatial profile of the analyte reached the maximum. The detection limits of the spectral lines commonly used for the determination of REE were measured and the spectral lines relatively free from spectral interferences were chosen.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2006.12a
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• pp.91-95
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• 2006

In whole world consciousness of environment maintenance have increased very quickly for the end of the 20th century. To use and disuse toxic substances have been controled at the field of industry. Also the field of lighting source belong to environmental control. And in the future the control will be strong. In radiational mechanism of fluorescence lamp mercury is the worst environmental problem. In radiational mechanism of fluorescence lamp mercury is the worst environmental problem root. In the mercury free lighting source system the Xe gas lamp is one type. And the Ne:Xe mixing gas lamp improvements firing voltage of Xe gas lamp. Purpose and subject of this study are understand, efficiency, ideal of Ne:Xe plasma which mercury free lamp. Before ICP was designed, basic parameters of plasma, which are electron temperature and electron density, were measured and calculated by langmuir probe data. Property of electron temperature and electron density were confirmed by changing ratio of Ne:Xe.

• Journal of Sensor Science and Technology
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• v.31 no.4
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• pp.214-217
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• 2022

The effect of inductively coupled plasma (ICP) treatment with O₂ gas on the surface properties of poly(ether sulfone) (PES) was investigated. X-ray photoelectron spectroscopy (XPS) was used to analyze the chemical characteristics of the O₂ plasma-treated PES films. The surface roughness of the pristine and O₂ plasma-treated PES films for different RF powers of the ICP was determined using an atomic force microscope (AFM). The contact angles of the PES films were also measured, using which the surface free energies were calculated. The O1s XPS spectra of the PES films revealed that the number of polar functional groups increased following the O₂ plasma treatment. The AFM analysis showed the average surface roughness increased from 1.01 to 4.48 nm as the RF power of the ICP was increased. The contact angle measurements revealed that the PES films became more hydrophilic as the RF power of the ICP was increased. The total surface energy increased with the RF power of the ICP, resulting from the increased polar energy component.

• 한국정보디스플레이학회:학술대회논문집
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• 2002.08a
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• pp.860-863
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• 2002

In this study, Ag thin films deposited on LCD-grade glass were etched using inductively coupled fluorine-based plasmas and the effect of various $CF_4$-based gas mixtures on the Ag etching characteristics were studied. When $CF_4$-based gas mixtures were used with $N_2$, due to the very low vapor pressure of etch products, etch products remained on the substrate after the etching. However, when $CF_4$ used with Ar, residue-free Ag etching could be obtained due to the removal of etch product by sputtering by $Ar^+$ ions.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.55 no.4
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• pp.204-208
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• 2006

In this study, we investigated the ion energy distributions in a chlorine based inductively coupled plasma by quadrupole mass spectrometer with an electrostatic ion energy analyzer. Ion energy distributions are presented for various plasma parameters such as $BCl_3/Ar$ gas mixing ratio, RF power, and process pressure. As the $BCl_3/Ar$ gas mixing ratio and process pressure decreases, and RF power increases, the saddle-shaped structures is enhanced. The reason is that there are ionized energy difference between $BCl_3$ and Ar, change of plasma potential, alteration of mean free path. and variety of ion collision in the sheath.