• Journal of Ginseng Research
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• 제45권4호
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• pp.519-526
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• 2021

Background: This study aimed to investigate the effect of cold plasma treatment on the improvement of seed germination and surface sterilization of ginseng seeds. Methods: Dehisced ginseng (Panax ginseng) seeds were exposed to dielectric barrier discharge (DBD) plasma operated in argon (Ar) or an argon/oxygen mixture (Ar/O₂), and the resulting germination and surface sterilization were compared with those of an untreated control group. Bacterial and fungal detection assays were performed for plasma-treated ginseng seeds after serial dilution of surface-washed suspensions. The microbial colonies (fungi and bacteria) were classified according to their phenotypical morphologies and identified by molecular analysis. Furthermore, the effect of cold plasma treatment on the in vitro antifungal activity and suppression of Cylindrocarpon destructans in 4-year-old ginseng root discs was investigated. Results: Seeds treated with plasma in Ar or Ar/O₂ exhibited a higher germination rate (%) compared with the untreated controls. Furthermore, the plasma treatment exhibited bactericidal and fungicidal effects on the seed surface, and the latter effect was stronger than the former. In addition, plasma treatment exhibited in vitro antifungal activity against C. destructans and reduced the disease severity (%) of root rot in 4-year-old ginseng root discs. The results demonstrate the stimulatory effect of plasma treatment on seed germination, surface sterilization, and root rot disease suppression in ginseng. Conclusion: The results of this study indicate that the cold plasma treatment can suppress the microbial community on the seed surface root rot in ginseng.

• Journal of Oral Medicine and Pain
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• 제41권3호
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• pp.126-132
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• 2016

Purpose: The aims of this study were to analyze the association between inflammatory cytokine and obstructive sleep apnea (OSA), and to evaluate treatment outcome and changes of plasma inflammatory cytokine levels after oral appliance therapy. Methods: Twenty-seven subjects who visited Department of Oral Medicine in Seoul National University Dental Hospital were performed nocturnal polysomnography and analyzed plasma C-reactive protein (CRP), interleukin (IL)-$1{\beta}$, IL-6, IL-10, and tumor necrosis factor (TNF)-${\alpha}$ levels. Each subject was evaluated with Pittsburgh Sleep Quality Index (PSQI) and Epworth Sleepiness Scale (ESS). The subjects were classified into 12 OSA patients (apnea-hypopnea index [AHI] >5) and 15 control (AHI ${\leq}5$) groups. The OSA group was treated with mandibular advancement device (MAD) for 3 months and re-evaluated nocturnal polysomnography and plasma inflammatory cytokine levels. Results: Plasma TNF-${\alpha}$, IL-10, and IL-6 levels were significantly higher in OSA patients compared to controls. Total AHI showed significant positive correlations with plasma IL-6 and TNF-${\alpha}$ levels. Percentage time of $SpO_2$ <90 and lowest $SpO_2$ were significantly correlated with plasma TNF-${\alpha}$ level. ESS showed significant positive correlation with plasma IL-10 level. Total AHI, percentage time of $SpO_2$ <90, lowest $SpO_2$, and mean $SpO_2$ were significantly improved after the MAD therapy. Plasma TNF-${\alpha}$ level was significantly decreased after MAD therapy. Conclusions: We suggest that MAD therapy is an effective treatment modality for patients with OSA and can decrease plasma cytokine level.

• 마이크로전자및패키징학회지
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• 제27권1호
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• pp.37-43
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• 2020

Fan-out wafer level packaging (FOWLP) 재배선 적용을 위한 Ti 박막과 WPR 절연층 사이의 계면 신뢰성을 평가하기 위해, O₂ 플라즈마 전처리 및 후속 열처리 시간에 따라 90° 필 테스트를 진행하였다. O₂ 플라즈마 전처리 시간이 증가 할수록 계면 접착력이 감소하다가 유지되는 거동을 보였으며, 이는 과도한 O₂ 플라즈마 전처리가 WPR 절연층 내의 C-O-C 또는 C=O 결합을 끊어 WPR 표면이 손상을 받아 계면 접착력이 저하된 것으로 판단된다. 또한 O₂ 플라즈마 전처리를 30초 진행한 시편을 150℃ 후속 열처리 진행한 결과, 계면 접착력이 0시간에서 24시간까지는 감소하였으나, 100시간까지 유지되는 거동을 보였다. 이는 고온에 취약한 WPR 절연층이 과도한 열처리로 인해 손상되어 계면 접착력이 급격히 감소하다가 유지되는 것으로 판단된다. 따라서, 절연층 소재에 대한 최적의 플라즈마 전처리 조건을 확보하는 것이 FOWLP 재배선의 계면신뢰성 향상을 위한 핵심요소임을 알 수 있다.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2006년도 6th International Meeting on Information Display
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• pp.74-77
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• 2006

Thin $AuO_x$ layer was formed by $O_2$ plasma treatment on Au electrode. The surface work function of plasma treatment showed higher by 0.5 eV than that of bare Au, reducing the hole injection barrier at the Au/pentacene interface. Using $O_2$ plasma-treated Au source-drain electrodes, the field-effect mobility of bottom-contact pentacene-OTFT was increased from 0.05 to 0.1 $cm^2/Vs$.

• Journal of Korean Vacuum Science & Technology
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• 제2권1호
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• pp.25-31
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• 1998

The reliability of fluorine doped silicon oxide (SiOF) films for intermetal dielectrics in multilevel interconnections of ultra-large scale integrated circuits (ULSIs) is investigated. SiOF films were deposited by electron cyclotron resonance plasma-enhanced chemical vapor deposition (ECRPECVD) using H-free source gases, i.e., SiF4 and O2. The effect of post plasma treatment on the moisture absorption and dielectric properties of SiOF films was carried out I terms of air exposure time, The reliability test of Cu/TiN/SiOF/Fi specimen was carried out in terms of temperature by rapid thermal annealing (RTA) in N2 ambient. After O2 plasma treatment,, no appreciable peak directly related to moisture absorption was detected. The capacitance-voltage (C-V) characteristics of the O2 plasma treated SiOF film showed that the film remained to hold the sound dielectric properties even after boiling treatment. The Cu/TiN/SiOF/Si system was found to be reliable up to $600^{\circ}C$.

• 마이크로전자및패키징학회지
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• 제16권2호
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• pp.21-25
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• 2009

The organic-inorganic thin film transistors (OITFTs) with ZnO channel layer and the cross-linked PVP (Poly-4-vinylphenol) gate insulator were fabricated on the patterned ITO gate/glass substrate. ZnO channel layer was deposited by using atomic layer deposition (ALD). In order to improve the electrical properties, $O_2$ plasma treatment onto PVP film was introduced and investigated the effect of the plasma treatments on the electrical properties of the OITFTs. The field effect mobility and sub-threshold slope (SS) values of the OITFT decreased slightly from 0.24 to 0.16 $cm^2/V{\cdot}s$ and from 9.7 to 9.2 V/dec, respectively with increasing RF power from 30 to 50 Watt. The $I_{on/off}$ ratio was about $10^3$ for all samples with $O_2$ plasma treatment.

• 한국재료학회지
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• 제14권5호
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• pp.363-367
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• 2004

Recently ZnO epitaxial layers have been widely studied as a semiconductor material for optoelectronic devices. Sapphire and silicon are commonly selected as substrate materials for ZnO epitaxial growth. In this communication, we report the effect of the ECR plasma pretreatment of sapphire and silicon substrates on the nucleation in the ZnO ALE (atomic layer epitaxy). It was found that ECR plasma pretreatment reduces the incubation period of the ZnO nucleation. Oxygen ECR plasma enhances ZnO nucleation most effectively since it increases the hydroxyl group density at the substrate surface. The nucleation enhancing effect of the oxygen ECR plasma treatment is stronger on the sapphire substrate than on the silicon substrate since the saturation density of the hydroxyl group is lower at the sapphire surface than that at the silicon surface.

• 조명전기설비학회논문지
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• 제22권8호
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• pp.75-81
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• 2008

본 논문은 플라즈마를 이용한 수처리 연구를 수행하였다. 이 연구에 사용한 수중플라즈마 토치는 상당한 전력의 절감을 가져올 수 있기 때문에 경제적인측면과 에너지효율면에서 뛰어난 결과를 나타내었다. 수중에서 일어나는 스트리머방전과 아크방전 현상을 면밀히 조사하여 비교하였고, 또한 염색페수를 플라즈마로 처리하였을 시의 색도제거율과 용존오존, 과산화수소와의 상관관계를 알기위해 표본화하고 분석하였다. 이에 플라즈마토치에는 선택적인 산화반응이 다소 있긴 하지만, 플라즈마화학반응에 의한 $H_2O_2$와 $O_3$의 성장이 아크방전 보다 스트리머방전시 더 효과적으로 촉진된다는 것을 알 수 있었다. 따라서 스트리머방전이 아크플라즈마 토치에 비해 더 효율적인 플라즈마 화학반응을 일으킬 수 있는 환경을 만들어주므로, 수처리에 있어서 스트리머플라즈마토치가 더 적합하였다.

• 반도체디스플레이기술학회지
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• 제18권1호
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• pp.32-37
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• 2019

Titanium dioxide ($TiO_2$) is a promising dielectric material in the semiconductor industry for its high dielectric constant. However, for utilization on Si substrate, $TiO_2$ film meets with a difficulty due to the large leakage currents caused by its small conduction band energy offset from Si substrate. In this study, we propose an in-situ plasma oxidation process in plasma-enhanced atomic layer deposition (PE-ALD) system to form an oxide barrier layer which can reduce the leakage currents from Si substrate to $TiO_2$ film. $TiO_2$ film depositions were followed by the plasma oxidation process using tetrakis(dimethylamino)titanium (TDMAT) as a Ti precursor. In our result, $SiO_2$ layer was successfully introduced by the plasma oxidation process and was used as a barrier layer between the Si substrate and $TiO_2$ film. Metal-oxide-semiconductor ($TiN/TiO_2/P-type$ Si substrate) capacitor with plasma oxidation barrier layer showed improved C-V and I-V characteristics compared to that without the plasma oxidation barrier layer.

• Current Photovoltaic Research
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• 제3권4호
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• pp.112-115
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• 2015

In this study, the surface of ITO films was modified using $N_2-O_2$ molecular plasma, and the effects of oxygen concentration in the plasma on the ITO surface properties were investigated. Upon plasma treatment of ITO films, the surface roughness of ITO films seldom changed up to the oxygen concentration in the range of 0% to 40%, while the roughness of the films slightly changed at or above the oxygen concentration of 60%. The contact angle of water droplet on ITO films dramatically changed with varying oxygen concentration in the plasma, and the minimum value was found to be at the oxygen concentration of 20%. The plasma resistance at this condition exhibited a maximum value, and the change of resistance showed an inverse relationship compared to that of contact angle. From these results, it was conjectured that the chemical reactions in the sheath of the molecular plasma dominated more than the physical actions due to energetic ion bombardment, and also the plasma resistance could be used as an indirect indicator to qualitatively diagnosis the state of plasma during the plasma treatment.