• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.24 no.2
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• pp.256-262
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• 2015

This study has an innovative improvement of the ocher tiles production system that aims to resolve social issue of industrial waste and to meet the customer needs for environmental-friendly building materials. By changing a wet type cutting method to a dry type of ocher tiles production system, the three processes such as cleaning, dehydration, and drying can be removed in existing overall process of 17 steps. Accordingly, the application of the wet type cutting method, which is proposed in this study, makes an increase in ocher tiles production from 1,500 to 1,850 pieces per hour. In particular, industrial wastewater that was emerging as the biggest problem in environmental pollutants in the wet cutting method has been removed. In addition, the most serious problems of noise and dust from the operator side, while developing a device for the dry cutting method, are eliminated through the development of additional equipment.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.20 no.3
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• pp.135-140
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• 2020

Since the process gas that is essential in the semiconductor process is a harmful gas, it is an essential task to solve it in an environmentally friendly manner. Currently, the cleaning technology used in the semiconductor process is mostly a wet cleaning based on hydrogen peroxide developed in the 1970s, and the SC-1 cleaning liquid for removing particles on the surface uses a mixture of ammonia and hydrogen peroxide. Therefore, environmental problems are caused, and economic problems caused by excessive water use are also serious. For this reason, the products developed through this study are used to decompose the process harmful gas from the chamber outlet into a harmless gas before entering the vacuum pump, or by incineration and the gaseous components are deposited on the pump. I want to solve the problem. In this paper, CPS (Confined Plasma Source) is proposed to save environment and improve productivity by replacing harmful gases (N2, CF4, SF6⋯., Etc) which are indispensable in semi-contamination process with innocuous gases or incineration with plasma, to study.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.41 no.12
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• pp.13-19
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• 2004

We have been studied on the high concentration ozonized water production technology which substitute for the SPM wet cleaning solution process as the PR strip process after the photolithography process in the semiconductor and flat panel display manufacturing. In this work, we have developed the surface discharge type ozone generator which has the characteristics of the 12 ［wt%］ ozone concentration at the oxygen gas flow of 0.5［ℓ/min］ oxygen per cell and also developed the high efficiency ozone contactor for the mixing ozone gas with deionized water. As the production test results of the ozonized water, we obtained the ozonized water concentration above 80［ppm］ at the 10［wt%］ ozone gas concentration, and also had a good result of the PR strip rate of 147［nm/min］. at the 70［ppm］ ozonized water.

• Particle and aerosol research
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• v.15 no.1
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• pp.1-13
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• 2019

Current desulfurization and denitrification technologies have reached a considerable level in terms of reduction efficiency. However, when compared with the simultaneous reduction technology, the individual reduction technologies have issues such as economic disadvantages due to the difficulty to scale-up apparatus, secondary pollution from wastewater/waste during the treatment process, requirement of large facilities for post-treatment, and increased installation costs. Therefore, it is necessary to enable practical application of simultaneous SOx and NOx treatment technologies to remove two or more contaminants in one process. The present study analyzes a technology capable of maintaining simultaneous treatment of SOx and NOx even at low temperatures due to the electrochemically generated strong oxidation of the wet-pulse complex system. This system also reduces unreacted residual gas and secondary products through the wet scrubbing process. It addresses common problems of the existing fuel gas treatment methods such as SDR, SCR, and activated carbon adsorption (i.e., low treatment efficiency, expensive maintenance cost, large installation area, and energy loss). Experiments were performed with varying variables such as pulse voltage, reaction temperature, chemicals and additives ratios, liquid/gas ratio, structure of the aeration cleaning nozzle, and gas inlet concentration. The performance of individual and complex processes using the wet-pulse discharge reaction were analyzed and compared.

• Journal of Conservation Science
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• v.26 no.2
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• pp.203-211
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• 2010

Analytic research on the surface pollutant of the three storied-pagoda at the west of Gameunsaji site as well as studies of previous wet cleaning cases was undertaken in order to decide cleaning method for removing inorganic pollutants. The status of pollutant was examined by naked eye observation, SEM-EDS, XRD. Then it was compared and categorized through qualitive and quantitative analysis. The result showed that the surface pollutants consisted of iron compounds or sulfur compounds and it was crystallized in the form of circle, oval, needle, etc. Result, Low-pressure rotating vortex process cleaning, with which particular matters are sprayed in swirl, is considered to be the best method to remove the pollutants.

• 연구논문집
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• s.33
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• pp.99-109
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• 2003

Recently the utilization of the ozone dissolved de-ionized water(DIW-$O_3$) in semiconductor wet cleaning process and photoresist stripping process to replace the conventional sulfuric acid and hydro peroxide mixture(SPM) method has been studied. In this paper, we propose the water-electrode type ozone generator which has the characteristics of the high concentration and purity to produce the high concentration DIW-$O_3$ for the photoresist strip process in the semiconductor fabrication. The proposed ozone generator has the dual dielectric tube structure of silent discharge type and the water is both used to electrode and cooling water. Through this study, we obtained the results of the 10.3 wt% of ozone gas concentration at the oxygen gas of 0.5 [liter/min.] and the DIW-$O_3$ concentration of 79.5 ppm.. Through the photoresist stripping test using the produced DIW-$O_3$, we confirmed that the photoresist coated on the silicon wafer was removed effectively in the 12 minutes.

• Journal of the Korean Society for Precision Engineering
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• v.26 no.5
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• pp.150-156
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• 2009

The removal of tiny particles adhered to surfaces is one of the crucial prerequisite for a further increase in IC fabrication, large area displays and for the process in nanotechnology. Various cleaning techniques (wet chemical cleaning, scrubbing, pressurized jets and ultrasonic processes) currently used to clean critical surfaces are limited to removal of micrometer-sized particles. Therefore the removal of sub-micron sized particles from silicon wafers is of great interest. For this purpose various cleaning methods are currently under investigation. In this paper, we report on experiments on the cleaning effect of 100nm sized fluorescence particles on silicon wafer using the plasma shockwave occurred by femtosecond laser. The plasma shockwave is main effect of femtosecond laser cleaning to remove particles. The removal efficiency was dependent on the gap distance between laser focus and surface but in some case surface was damaged by excessive laser intensity. These experiments demonstrate the feasibility of femtosecond laser cleaning using 100nm size fluorescence particles on wafer.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1999.11a
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• pp.617-620
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• 1999

To reduce the consumption of chemicals and ultra pure water(UPW) in cleaning process used in device manufacturing, we proposed wet processes that use electrolytic ionized water(EIW), which is generated by electrolysis of a diluted electrolyte solution or UPW and systemically investicate the EIW\`s characteristics. EIW\`s pH values are increased in cathode chamber and decreased in anode chamber according to the electrolysis time and its varied ratio is reduced with time increasement. The variation of pH and ORP is increased accordin to the applied voltage until critical voltage. But more than that voltage, the variation is decreased because of ion\`s scattering effect. When electrolyte is added, the effects of electrolysis is increased because electrolyte acts as catalyst. But when the density of electrolyte is increased more than critical value, ion\`s flowage is obstructed and the effects of electrolysis is decreased.

• Proceedings of the KIEE Conference
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• 1997.07d
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• pp.1528-1530
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• 1997

As device size shrinks, contamination will increasingly affect the reliability and yield of device. Therefore, contaminants must be removed from the surfaces of Si wafers prior to each process. But it becomes out increasingly difficult to clean silicon surfaces with finer patterns by the conventional wet treatment because of the viscosity and surface tension of solutions. Hence, a damage less dry cleaning process is needed for the silicon surfaces. For the removal of Si native oxide by UV-enhanced dry cleaning. $F_2$ gas and $F_2/H_2$ mixed gas were applied. As a result of analysis, UV-enhnaced $F_2/H_2$ treatment is more suitable than UV-enhanced $F_2$ treatment for removal of native oxide on the surfaces of Si wafers.

• Journal of Advanced Marine Engineering and Technology
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• v.41 no.3
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• pp.216-221
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• 2017

Diesel engines have the highest brake thermal efficiency among internal combustion engines. Therefore, they are utilized in medium and large transportation vehicles requiring large amounts of power such as heavy trucks, ships, power generation systems, etc. However, diesel engines have a disadvantage of generating large quantities of nitrogen oxides during the combustion process. Therefore, the authors tried to reduce the amount of nitrogen oxides in marine diesel engines using a wet-type exhaust gas cleaning system utilizing the undivided electrolyzed seawater method. In this method, electrolyzed seawater in injected into the harmful gas discharge from the diesel engine using real seawater. The authors investigated the reduction of NO and NOx from the pH value, available chlorine concentration, and the temperature of electrolyzed seawater. The results of this experiment indicated that when the electrolyzed seawater is acidic, the NO oxidation rate in the oxidation tower is higher than that when the electrolyzed seawater has a neutral pH. Likewise, the NO oxidation rate increased with the increase in concentration of chlorine. Further, it was confirmed that the electrolyzed seawater temperature had no effect on the NO oxidation rate. Thus, the NOx exhaust emission value produced by the diesel engine was reduced by means of electrolyzed seawater treatment.