• Proceedings of the Korean Vacuum Society Conference
• /
• 2011.02a
• /
• pp.261-262
• /
• 2011

본 연구는 HMDS/$O_2$/He/Ar의 gas mixture를 이용하여 remote-type의 DBD source를 통한 APPECVD를 통한 SiOx 양질의 무기막 증착 공정을 개발하였다. 이때 기판에 바이어스를 인가 하거나 혹은 접지를 하여 대기압 플라즈마의 환경 내에서도 바이어스 효과를 확인할 수 있도록 double discharge system을 구축하였다. 그리고 이 double discharge system의 다양한 특성과 기존의 전형적인 DBD와 비교 하였을 때 어떠한 차이점을 가지는지에 대해서도 관찰하였다. 그리하여 전형적인 DBD system과 double discharge를 통해 증착된 SiOx 무기막의 특성을 역시 비교 관찰하였다. Gas mixture 중 HMDS의 유량이 증가함에 따라, 그리고 $O_2$ gas의 유량이 감소함에 따라 SiOx 무기막의 증착률은 감소하였다. 그러나, SiOx 무기막 내의 불순물들, 예를 들어, carbon 혹은 hydrogen 계열의 chemical bond에 대한 정성적인 양은 HMDS 의 유량이 증가하거나 혹은 $O_2$ gas의 양이 감소함에 따라 오히려 증가함을 관찰할 수 있었다. 그리고 기판에 바이어스를 인가하는 double discharge system을 사용하였을 경우, 같은 HMDS, $O_2$ gas 유량을 사용한 전형적인 DBD type의 증착 공정 보다 더 높은 공정 효율을 나타냄과 동시에 더 낮은 불순물 함량을 가짐을 알 수 있었다. 이러한 double discharge system을 통해 증착된 양질의 SiOx 무기막이 증착 되었음을 FT-IR을 통한 막질 분석을 통해 확인 할 수 있었다. 이러한 double discharge system의 증착 공정에 대한 긍정적인 효과들은 atmospheric discharge의 효율 향상에 따른 gas dissociation efficiency 증가와 이를 통한 HMDS 분해 및 산소와의 recombination 효율의 증가에 따른 결과로 사료된다.

• Journal of Korean Society for Atmospheric Environment
• /
• v.17 no.2
• /
• pp.223-231
• /
• 2001

In order to provide some insights into the influence of electric field, gas composition, and gas temperature on electron energy distribution and electron transport characteristics, the Boltzmann equation was solved by using cross section data for electron collisions, Critical electric fields for the corona development in dry air and flue gas are 150 and 80 Td, respectively. It was seen that the decrease of critical electric field in flue gas is mainly caused by the $H_2O$ addition through the comparison of ionization and attachment coefficients of gas components. Increase of $O_2$, $H_2O$, and $CO_2$ contents in gas affected discharge characteristics according to their reciprocal characteristics between lowering the ionization threshold and increasing the electro-negativity. As electric field increases, electrons with higher energies in the electron energy distribution also increase. The mean and characteristic electron energies also linearly increase with electric field. The variation of flue gas temperature did rarely affect on the electron energy distribution function and electron transport characteristics, because the gas temperature is several hundreds or thousands times lower than the electron temperature.

• Proceedings of the KSR Conference
• /
• 2000.11a
• /
• pp.740-747
• /
• 2000

This paper describes insulation characteristics and partial discharge for the SF6 gas insulated transformer. The characteristic of gas insulated transformer and the degradation sequence of solid insulation under SF6 gas atmosphere were explained. The model electrode system of the types that the aramid papers were inserted between two sphere electrodes was prepared. The partial discharge tests were carried out to that system and the insulation characteristics were considered.

• 한국정보디스플레이학회:학술대회논문집
• /
• 2002.08a
• /
• pp.586-589
• /
• 2002

The Ultra Violet(UV) emission characteristics of Neon + Nitrogen gas-mixture discharge was investigated in AC plasma display panel. The firing voltage of Ne+$N_2$ gas-mixture discharge increased with increasing nitrogen concentration. The UV intensity emitted from the gas discharge also increased with increasing nitrogen concentration. The UV efficiency increase with increasing $N_2$ partial pressure at low $N_2$ concentration, and then UV efficiency is saturated at high $N_2$ concentration.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
• /
• v.11 no.3
• /
• pp.248-254
• /
• 1998

In the present study the glow discharge characteristics of $CO_2$ in a parallel plate electrode system were investigated, and the decomposition properties of $CO_2$ concerned with the discharge characteristics were discussed. The results show that $CO_2$ concentration decreases with increase in discharge power and decrease in gas pressure. The maximum conversion of $CO_2$ by glow discharge was 52% under the conditions of gas pressure, 10m Torr and 290W of discharge power.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2005.06a
• /
• pp.1571-1574
• /
• 2005

Generally, the kerosene or the deionized water has been used for dielectric fluid in the electrical discharge machining. The spark occurs when the voltage is over the breakdown voltage and induces high temperature. In this study, the Oxygen gas is used as the dielectric. The voltage behavior in the dry Micro Electrical discharge machining is compared with that of the conventional Micro Electrical discharge machining. The dry Micro EDM has some advantages. The electrode wear isvery smaller than that of the conventional Micro EDM. The contamination in the dry Micro EDM can be drastically reduced comparing to that of the conventional Micro EDM. The Oxygen gas can be replaced as the dielectric successfully.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
• /
• v.21 no.9
• /
• pp.18-24
• /
• 2007

When faults occur in the power equipment that is used a great deal in industrial sites, it may lead to fatal accidents that cause losses both economically and in manpower. In this paper, the effect of particle impact on the partial discharge of $SF_6$ gas was measured by simulating a partial discharge following the type of fault found in the GIS using $SF_6$ insulating gas as the insulating material. A spectrum analysis was performed on the radiate electromagnetic waves emitted upon partial discharge by using the UHF insulation diagnosis method. This subject of this study is insulation diagnosis by the measurement of radiate electromagnetic waves when particles exist in the GIS and power equipment insulated with $SF_6$ gas.

• Journal of the Korean Society of Industry Convergence
• /
• v.15 no.2
• /
• pp.49-54
• /
• 2012

With the improvement of industrial society, the high quality electrical energy, simplification of operation and maintenance, ensuring reliability and safety are being required. This paper reviews a basic data of the surface discharge characteristics for teflon resin in not only pure $N_2$, $N_2:O_2$ mixture gas and Dry-Air as being focused on environmentally friendly insulating Gas also $SF_6$. Used electrodes are Knife to Knife. With the changing distance of electrodes and pressure, we can find it, surface discharge voltages and surface dielectric strengths, respectively. Surface discharge Voltages of $N_2:O_2=80:20$ mixture gas are more higher than the $N_2:O_2$ Mixture gases.

• Journal of Industrial Technology
• /
• v.18
• /
• pp.249-258
• /
• 1998

In this paper, we investigated the post-combustion removal of nitrogen oxide($NO_x$) and sulfur oxide($SO_x$) which is based on the gas to particle conversion process by the pulsed corona discharge. Under normal pressure, the pulsed corona discharge produces the energetic free electrons which dissociate gas molecules to form the active radicals. These radicals cause the chemical reactions that convert $SO_x$ and $NO_x$ into acid mists and these mists react with $NH_3$ to form solid particles. Those particles can be removed from the gas stream by conventional devices such as electrostatic precipitator or bag filter. The reactor geometry was coaxial with an inner wire discharge electrode and an outer ground electrode wrapped on a glass tube. The simulated flue gas with $SO_x$ and $NO_x$ was used in the experiment. The corona discharge reactor was more efficient in removing $SO_x$ and $NO_x$ by adding $NH_3$ and $H_2O$ in the gas stream. We also measured the removal efficiency of $SO_x$ and $NO_x$ in a cylinder type corona discharge reactor and obtained more than 90 % of removal efficiency in these experimental conditions. The effects of process variables such as the inlet concentrations of $SO_x$, $NH_3$ and $H_2O$, residence time, pulse frequencies and applied voltages were investigated.

• The Transactions of the Korean Institute of Electrical Engineers
• /
• v.38 no.6
• /
• pp.470-476
• /
• 1989

In order to develop a mathematical model which can predict the operating voltage and current of a discharge lamp, the properties and the physical phenomena of a low pressure gas discharge are investigated. Fluorescent lamp which uses a low pressure mercury-argon gas discharge is used in the model development. In a low pressure mercur-argon gas discharge, the continuity equation for each excited atom and electron, and the electron energy balance equation can predict the physical quantities of discharge. By coupling these equations and the circuit equation, the electrical characteristics of the discharge lamp can be predicted. To verify the validity of the suggested model, we calculated the voltage and current of a fluorescent lamp operating with inductor ballast for source frequency of 5KHz, 8KHz, 10KHz, and 13KHz. The results show good agreements in wave forms between the measured voltage and current, and the difference between the measured and calculated one is less than 5%.