• 한국진공학회:학술대회논문집
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• 한국진공학회 1999년도 제17회 학술발표회 논문개요집
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• pp.220-220
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• 1999

In plasma source ion implantation, the target is immersed in the plasma and repetitively biased by negative high voltage pulses to implant the extracted ions from plasma into the surface of the target material. In this way, the problems of line-of-sight implantation in ion-beam ion implantation technique can be effectively solved. In addition, the high dose rate and simplicity of the equipment enable the ion implantation a commercially affordable process. In this work, plasma source ion implantation technique was used to improve the wear resistance of Co-cemented WC. which has been extensively used for high speed tools. Nitrogen and carbon ions were implanted using the pulse bias of -602kV, 25 sec and at various implantation conditions. The implanted samples were examined using scanning Auger electron spectroscopy and XPS to investigate the depth distributions of implanted ions and to reveal the chemical state change due to the ion implantation. The implanted ions were found to have penetrated to the depth of 3000$\AA$. The wear resistance of the implanted samples was measured using pin-on-disc wear tester and the wear tracks were examined with alpha-step profilometer.

• 한국세라믹학회지
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• 제45권11호
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• pp.707-712
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• 2008

Plasma resistant nanocrystalline $Y_2O_3$ films were deposited on alumina substrates through the electron-beam PVD technique. Increasing substrate temperature to $600^{\circ}C$ resulted in the textured microstructures with significantly enhanced adhesion force of the coating to the substrate. During the exposure to fluorine plasma, erosion rate of the coated specimen was higher than that of a sintered yttria specimen, but significantly lower than that of a single crystalline alumina. Considering the adhesion and erosion behaviors observed in the coated specimen prepared at $600^{\circ}C$, the deposition technique appears effective in reducing contamination particles generated from the ceramic parts in the plasma environment.

• 한국결정성장학회:학술대회논문집
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• 한국결정성장학회 1998년도 PROCEEDINGS OF THE 14TH KACG TECHNICAL MEETING AND THE 5TH KOREA-JAPAN EMGS (ELECTRONIC MATERIALS GROWTH SYMPOSIUM)
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• pp.65-70
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• 1998

The Spray-ICP technique uses the ICP(Inductively Coupled Plasma) of ultra-high temperature which is produced by r.f power. The ICP is well-kwown as a clean heat source for the preparation of pure ceramic particles because the ICP is a electrodeless-thermal plasma without contamination. In this study,{{{{ { SnO}_{2 } }}}} particles were sythesized from metal salt solution by Spray-ICP technique. The effects of concentration of solution, collecting location of powders were investicated. The prepared {{{{ { SnO}_{2 } }}}} particles from each concentration of solution had same crystalline phase(tetragonal {{{{ { SnO}_{2 } }}}}) a nd the mean size decreased in proportion to the increase of solution concentration. Each {{{{ { SnO}_{2 } }}}} p owders collector in reactor and electrostatic collector had same crystalline phase and morphologies. The mean size of {{{{ { SnO}_{2 } }}}} p articles prepared by Spray-ICP technique was below 30nm.

• Transactions on Electrical and Electronic Materials
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• 제1권1호
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• pp.6-11
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• 2000

The hydrogen plasma treatment of silicon wafers in the reactive ion-etching mode was studied for the application to silicon-on-insulator wafers which were prepared using the wafer bonding technique. The chemical reactions of hydrogen plasma with surface were used for both surface activation and removal of surface contaminants. As a result of exposure of silicon wafers to the plasma, an active oxide layer was found on the surface. This layer was rendered hydrophilic. The surface roughness and morphology were examined as functions of the plasma exposing time and power. In addition, the surface became smoother with the shorter plasma exposing time and power. The value of initial surface energy estimated by the crack propagation method was 506 mJ/㎡, which was up to about three times higher as compared to the case of conventional direct using the wet RCA cleaning method.

• The Korean Journal of Ceramics
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• 제4권1호
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• pp.20-24
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• 1998

Thin films of diamond-like carbon(DLC) can be successfully deposited by using a magnetron plasma chemical vapor deposition (CVD) method with an rf(13.56 MHz) plasma of $C_dH_8$. Plasma characteristics are analyzed as a function of the magnetic field. As the magnetic field increases, both electron temperature ($T_e$) and density ($n_e$)increase, but the negative dc self-bias voltage (-$V_{ab}$) decreases, irrespective of gas pressures in the range of 1~7 mTorr. High deposition rates have been obtained even at low gas pressures, which may be attributed to the increased mean free path of electrons in the magentron plasma. Effects of rf power and additive gas on the structural properties of DLC films aer also examined by using various technique namely, TED(transmissio electron diffraction) microanalysis, FTIR, and Raman spectroscopies.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2011년도 제41회 하계 정기 학술대회 초록집
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• pp.144-144
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• 2011

Diagnostics of plasma density and temperature play an important role for monitoring plasma processing and Laser Thomson scattering is a one of the most accurate diagnostic technique for measuring plasma density and temperature because of none-perturbation to plasma among various diagnostic techniques invented to measure plasma density and temperature. I will briefly review Laser Thomson scattering experiment performed in KRISS and difficulties for measuring the electron velocity distribution such as Gaussian due to low signal-to-noise ratio with showing results that we got until now. This work is an intermediate step in a process that we will get a reliable data which shows physical phenomenon of plasma compared with other diagnostic techniques and results.

• 한국환경과학회지
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• 제26권6호
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• pp.711-717
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• 2017

Dielectric Barrier Discharge (DBD) plasma is a new technique for use in environmental pollutant degradation, which is characterized by the production of hydroxyl radicals as the primary degradation species. Due to the short lifetime of the chemically active species generated during the plasma reaction, the dissolution of the plasma gas has a significant effect on the reaction performance. The plasma reaction performance can be enhanced by combining the basic plasma reactor with a homogenizer system in which the bubbles are destroyed and turned into micro-bubbles. For this purpose, the improvement of the dissolution of plasma gas was evaluated by measuring the RNO (N-dimethyl-4-nitrosoaniline, an indicator of the generation of OH radicals). Experiments were conducted to evaluate the effects of the diameter, rotation speed, and height of the homogenizer, pore size, and number of the diffuser and the applied voltage on the plasma reaction. The results showed that the RNO removal efficiency of the plasma reactor combined with a homogenizer is two times higher than that of the conventional one. The optimum rotor size and rotation speed of the homogenizer were 15.1 mm, and 19,700 rpm, respectively. Except for the lowest pore size distribution of $10-16{\mu}m$, the pore size of the diffuser showed little effect on RNO removal.

• Macromolecular Research
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• 제17권1호
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• pp.31-36
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• 2009

Highly transparent, thin polythiophene (PT) films were successfully synthesized by the plasma polymerization of thiophene. These films were doped with $O_2$ plasma by in-situ doping technique. The plasma polymerized PT films were deposited at about 50 to 340 nm/min, depending on the temperature and plasma power. A resultant transparency as high as 85% was achieved. The plasma polymerized PT films exhibited the characteristics of an insulator or semiconductor ($10^{10{\sim}12}{\Omega}/{\Box}$, $10^{-7}S/cm$). The conductivity was immediately increased up to $10{\Omega}/{\Box}$ and $10^{-2}S/cm$, when doped with $O_2$ plasma. The plasma-doped PT films exhibited an increased surface roughness resulting in a decreased contact angle. However, the thickness of the PT layer was partially decomposed and/or etched with increasing voltage above 40 W.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2004년도 하계학술대회 논문집 C
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• pp.1874-1875
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• 2004

A high rate deposition sputtering process of magnesium oxide thin film in oxide mode has been developed using a 20 kW unipolar pulsed power supply. The powersupply was operated at a maximum constant voltage of 500 V and a constant current of 40 A. The pulse repetition rate and the duty were changed in the ranges of 10 ${\sim}$ 50 kHz and 10 ${\sim}$ 60 %, respectively. The deposition rate increased with increasing incident power to the target. Maximum incident power to the magnesium target was obtained by the control of frequency, duty and current. The deposition rate of a moving state was 9 nm m/min at the average power of 1.5 kW. This technique is proposed to apply high through-put sputtering system for plasma display panel.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1988년도 추계학술대회 논문집 학회본부
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• pp.189-192
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• 1988

Nitrided oxides have been investigated recently for application as a replacement for thermally grown $SiO_2$ in MIS devices. In this paper, thin oxides were nitrided in $N_2$ Plasma ambient. With the measurement of the equivalent paralled conductance and capacitance by the using coductance technique, the characterization of Si-SiON interface is developed. The interface state density of Si-SiON is obtained by $1{\times}10^{11}{\sim}9{\times}10^{11}(eV^{-1}Cm^{-2})$. After${\pm}$B-T stress is performed on the sample, the interface state density gets increased.