• Optical Science and Technology
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• v.18 no.3
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• pp.10-13
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• 2014

• Journal of the Semiconductor & Display Technology
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• v.15 no.3
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• pp.35-39
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• 2016

Extreme Ultraviolet Lithography (EUVL) is the most promising technique in the field of Next Generation Lithography (NGL) expected to be used in the 1x-nm node for High Volume Manufacturing (HVM). But there exits remaining challenges for proper defect control of EUV mask. It was considered development of EUV pellicle for protecting the EUV mask has many obstacles due to high extinction coefficient of EUV wavelength. Recently researchers in the industry of semiconductor argue about the necessity of EUV pellicle and make effort to achieve it. In this paper, we investigated that the relationship between imaging performance and transmittance of EUV pellicle quantitatively. We made in-house EUV pellicle and analyzed its imaging performance of the dependence of pellicle transmittance using Coherent Scattering Microscopy(CSM). The imaging performance of EUV mask with pellicle is affected by its transmittance and we found that the performance of EUV mask improved with higher transmittance pellicle.

• Journal of the Semiconductor & Display Technology
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• v.15 no.1
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• pp.17-21
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• 2016

EUV (Extreme Ultraviolet) pellicle which protects a mask from contamination became a critical issue for the application of EUV lithography to high-volume manufacturing. However, researches of EUV pellicle are still delayed due to no typical manufacturing methods for large-scale EUV pellicle. In this study, EUV pellicle membrane manufacturing method using not only KOH (potassium hydroxide) wet etching process but also a water bath was suggested for uniform etchant temperature distribution. KOH wet etching rates according to KOH solution concentration and solution temperature were confirmed and proper etch condition was selected. After KOH wet etching condition was set, $5cm{\times}5cm$ SiNx (silicon nitride) pellicle membrane with 80% EUV transmittance was successfully manufactured. Transmittance results showed the feasibility of wet etching method with water bath as a large-scale EUV pellicle manufacturing method.

• Korean Journal of Materials Research
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• v.25 no.9
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• pp.462-467
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• 2015

Pellicle is defined as a thin transparent film stretched over an aluminum (Al) frame that is glued on one side of a photomask. As semiconductor devices are pursuing higher levels of integration and higher resolution patterns, the cleaning of the Al flame surface is becoming a critical step because the contaminants on the Al flame can cause lithography exposure defects on the wafers. In order to remove these contaminants from the Al frame, a highly concentrated nitric acid ($HNO_3$) solution is used. However, it is difficult to fully remove them, which results in an increase in the Al surface roughness. In this paper, the pellicle frame cleaning is investigated using various cleaning solutions. When the mixture of sulfuric acid ($H_2SO_4$), hydrofluoric acid (HF), hydrogen peroxide ($H_2O_2$), and deionized water with ultrasonic is used, a high cleaning efficiency is achieved without $HNO_3$. Thus, this cleaning process is suitable for Al frame cleaning and it can also reduce the use of chemicals.

• Journal of Naturopathy
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• v.13 no.1
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• pp.42-50
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• 2024

Background: Kombucha, originating from Northeast Asia, is a fermented beverage produced by fermenting black tea with a symbiotic culture of bacteria and yeast, renowned for its myriad health benefits. The augmentation of its health-promoting attributes, particularly antioxidant properties, through the integration of medicinal herb extracts, has gained attention in recent research. Purpose: The objective of this research was to explore the potential enhancement of the antioxidant properties of kombucha through the addition of hot water extracts from selected 7 medicinal herbs native to Jeju Island. Additionally, the study aimed to ascertain the successful transfer of active herbal ingredients into the kombucha. Methods: The methodology entailed the hot water extraction of the aforementioned medicinal herbs followed by their incorporation into the kombucha during a secondary fermentation phase. The assessment criteria included the analysis of the kombucha's physical characteristics post-fermentation, the quantification of sugar content, and the evaluation of antioxidant using DPPH, ABTS assays. The presence of specific active compounds(EGCG, 2,5-DHAP) was verified using HPLC and SDS-Gel Electrophoresis. Results: The findings indicated a successful fermentation process, as evidenced by an increase in reducing sugars. Moreover, the kombucha exhibited notable antioxidant activities post-fermentation, which implies the effective infusion of the herbal extracts' properties into the beverage. HPLC and electrophoresis analysis confirmed the assimilation of key active ingredients from the herbs into the kombucha. Conclusions: This study substantiates the premise that the enrichment of kombucha with hot water extracts from Jeju Island's medicinal herbs enhances its antioxidant properties. The successful integration of these herbal components into kombucha not only amplifies its health benefits but also contributes to the expansion of the functional beverage sector within the domains of health and alternative medicine.