• 한국생산제조학회지
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• 제22권4호
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• pp.643-651
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• 2013

This study applied a laser cleaning method (dry cleaning) that is used for cleaning semiconductor elements to dental implant cleaning. The lasers used in this study were pulsed fiber lasers with wavelengths of 1,064 and 532 nm. The peak output, energy per pulse, energy density per pulse, time of pulse experiment, and number of pulse experiments served as process variables for this study, and the variables were changed for each experiment. As a result, a laser with a wavelength of 532 nm showed much higher cleaning efficiency than its 1,064 nm counterpart. As the wavelength range decreased, the quantized energy increased and the reflection rate of the titanium used for the implant decreased; consequently, the energy absorption rate increased. Therefore, it is proposed that the energy density by wavelength has a greater influence on cleaning than does the output size.

• 한국레이저가공학회지
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• 제6권3호
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• pp.29-35
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• 2003

In semiconductor processing, there are two types of particle contaminated onto the wafer, i.e. dry and wet state particles. In order to evaluate the cleaning performance of laser shock wave cleaning method, the removal of 1 m sized alumina particle at different particle conditions from silicon wafer has been carried out by laser-induced shock waves. It was found that the removal efficiency by laser shock cleaning was strongly dependent on the particle condition, i.e. the removal efficiency of dry alumina particle from silicon wafer was around 97％ while the efficiencies of wet alumina particle in DI water and IPA are 35％ and 55％ respectively. From the analysis of adhesion forces between the particle and the silicon substrate, the adhesion force of the wet particle where capillary force is dominant is much larger than that of the dry particle where Van der Waals force is dominant. As a result, it is seen that the particle in wet condition is much more difficult to remove from silicon wafer than the particle in dry condition by using physical cleaning method such as laser shock cleaning.

• 반도체디스플레이기술학회지
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• 제4권4호
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• pp.13-17
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• 2005

The behavior of ozone in $NH_4OH$ was investigated to evaluate the solution as a cleaning chemical of the silicon wafer. The solubility of ozone in DI(Deionized) water increased as the oxygen flow-rate decreased and ozone generator power increased. Ozone in DI water showed solubility of 100 ppm or higher at room temperature. Ozone concentration was stabilized at the range of ${\pm}2ppm$ by controlling oxygen flow rate and ozone generator power. On the contrary, the solubility of ozone in $NH_4OH$ was very low and strongly depended on the concentration of $NH_4OH$ and pH. The redox potential of ozone was saturated within 10 minutes in DI water and decreased rapidly with the addition of $NH_4OH$. The behavior of ozone in $NH_4OH$ is well explained by redox potential calculation.

• 반도체디스플레이기술학회지
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• 제10권3호
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• pp.15-19
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• 2011

The performance of the DRAM is strongly dependent on the purity and surface roughness of the TIT (TiN/Insulator/ TiN) capacitor electrodes. Hence, in the present study, we evaluate the effects of organic contamination and change of surface roughness on the cylindrical TIT capacitor electrodes during the wet cleaning process by various analytical techniques such as TDMS, AFM, XRD and V-SEM. Once the sacrificial oxide and PR (Photo Resist) are removed by HF, the organic contamination and surface oxide films on the bottom Ti/TiN electrode become visible. With prolonged HF process, the surface roughness of the electrode is increased, whereas the amount of oxidized Ti/TiN is reduced due to the HF chemicals. In the 80nm DRAM device fabrication, the organic contamination of the cylindrical TIT capacitor may cause defects like SBD (Storage node Bridge Defect). The SBD fail bit portion is increased as the surface roughness is increased by HF chemicals reactions.

• 반도체디스플레이기술학회지
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• 제20권3호
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• pp.140-145
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• 2021

This paper deals with the development of a deep-learning-based runway cleaning robot using an optical camera. A suitable model to realize real-time object detection was investigated, and the differences between the selected YOLOv3 and other deep learning models were analyzed. In order to check whether the proposed system is applicable to the actual runway, an experiment was conducted by making a prototype of the robot and a runway model. As a result, it was confirmed that the robot was well developed because the detection rate of FOD (Foreign Object Debris) and cracks was high, and the collection of foreign substances was carried out smoothly.

• 반도체디스플레이기술학회지
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• 제23권2호
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• pp.100-106
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• 2024

To generate the plasma required in dry cleaning processes, the plasma chamber must be supplied with a high-quality AC voltage with a voltage of more than 1 kV and a frequency of 400 kHz. In the existing research, many methods to supply high power have been studied, but how to improve the quality of the power for high-quality plasma has been relatively little studied. In this paper, we propose a study to improve the quality of RF power circuit for high-quality plasma generation in dry cleaning method. Existing methods in the environment of full-bridge-based RF power circuits must perform PWM duty control in the light load region. This causes distortions in the waveform, resulting in poor power quality, which directly leads to poor plasma quality. To solve these problems, a half-bridge switching method is proposed and the improvement in waveform quality is verified. To verify the feasibility of the design and control algorithm proposed in this paper, an RF power circuit prototype is fabricated and the proposed design and control method is verified through simulation and actual experiments under dummy load.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1995년도 하계학술대회 논문집 C
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• pp.1069-1071
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• 1995

The electrical properties of Al/TiN/Ti contact are investigated at submicron contacts. The contact resistance and contact leakage current are dependent on metallization, surface dopant concentration, semiconductor surface treatment and contact plug ion implantation. In this paper, the contact resistance and contact leakage current are studied according to surface dopant concentration, semiconductor surface treatment and contact plug ion implantation at 0.8 micron contact. The contact resistance and contact leakage current increases with increasing substrate ion concentration. HF cleaning represents high contact resistance but low contact leakage current while CDE cleaning represents low contact resistance but high contact leakage current. Contact plug ion implantation decreases contact resistance but increases contact leakage current. Specially, RTA represents good electrical properties.

• 한국지능시스템학회:학술대회논문집
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• 한국퍼지및지능시스템학회 2004년도 춘계학술대회 학술발표 논문집 제14권 제1호
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• pp.149-152
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• 2004

Generally the wafer is increased by 300mm. We are desired that the wafer is prevented from pollutions of metal contaminant on surface of wafer. We have to develop new wafer cleaning process of IC Manufacturing that can reduce DI water and chemical by removal of the wafer cleaning process step. Moreover, it is difficult to control temprature and density of chemical in spite of rapidly increasing automation of system. We design smart module controller for new generation of semiconductor wet station with intelligent algorithm using data that is taken by computer simulation for optimal system.

• 한국반도체및디스플레이장비학회:학술대회논문집
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• 한국반도체및디스플레이장비학회 2005년도 춘계 학술대회
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• pp.157-162
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• 2005

The wafer's size has been increased up to 300mm according as the devices have been integrated sophisticatedly. For this process to make 300mm-wafer, it is required strict level which removes the particulates on the surface of wafer. Therefore we need new type wet-station which can reduce DI water and chemical in the cleaning process. Moreover, it is very important to control the temperature and the concentration of chemical wet-stat ion. The chemical supply system which is used currently is not only difficult to make a fit mixing rate of chemical in cleaning process, but also it is difficult to make fit quantity and temperature. We propose new chemical supply system, which overcomes the problems via analysis of fluid and thermal transfer on chemical supply system,

• 반도체디스플레이기술학회지
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• 제6권2호
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• pp.5-10
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• 2007

According to the advantageous features of flash memory, its exploitation and application in mobile and ubiquitous related devices as well as voluminous storage devices is being increased rapidly. The inherent properties that are determined by configuration of flash memory unit might restrict the promising expansion in its utilization. In this paper, we study policies based on threshold values, instead of using global search, in order to satisfy our objective that is to decrease the necessary processing cost or penalty for recycling of flash memory space at the same time minimizing the potential degradation of performance. The proposed cleaning methods create partitions of candidate memory regions, to be reclaimed as free, by utilizing global or dynamic threshold values. The impact of the proposed policies is evaluated through a number of experiments, the composition of the optimal configuration featuring the methods is tested through experiments as well.