• 반도체디스플레이기술학회지
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• 제22권4호
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• pp.131-135
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• 2023

Neural network-based time series models called time series neural networks (TSNNs) are trained by the error backpropagation algorithm and used to predict process shifts of parameters such as gas flow, RF power, and chamber pressure in reactive ion etching (RIE). The training data consists of process conditions, as well as principal components (PCs) of optical emission spectroscopy (OES) data collected in-situ. Data are generated during the etching of benzocyclobutene (BCB) in a SF₆/O₂ plasma. Combinations of baseline and faulty responses for each process parameter are simulated, and a moving average of TSNN predictions successfully identifies process shifts in the recipe parameters for various degrees of faults.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2003년도 International Meeting on Information Display
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• pp.207-212
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• 2003

The field emission and luminescent properties of carbon nanotubes (CNTs) that were straightened out by argon ion irradiation were investigated. Argon ion irradiation permanently straightened out both as-grown and screen-printed CNTs in the presence of a strong electric field. The straightening process enhanced the emission properties of CNT films by showing a decrease in turn-on field, an increase in total emission current, and a stable emission. Furthermore, the number of emission sites was confirmed to increase by observing the luminescent properties of CNT films after the straightening. The mechanism involved in the straightening of the CNTs is proposed and the enhancement in field emission is discussed in detail.

• 한국건설순환자원학회논문집
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• 제2권2호
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• pp.93-100
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• 2006

Building materials are trending toward environmental materials nowadays and the market share of those is growing. So those researches and developments for environmental property are proceeding now. The main properties of environmental products are far infrared emission, negative ion emission, electro magnetic wave shielding, and anti fungus, these products are used with shape of mortar, and spray on the finish material. But There are not much researches for the concrete, main material in construction field, with those functional properties. So in this research we evaluated slump, compressive strength and air content as basic properties for concrete using functional materials of sericite, wood pattern sand stone, carbon black and nanometric silver solution and functional properties like far infrared emission, negative ion emission, electro magnetic wave shielding, and anti fungus. The results were as follows. The most useful material in the functional materials was carbon black. Sericite and nanometric silver solution had a little effect on functional property, so it was difficult to apply to concrete, and wood pattern sand stone had a high functional property but low compressive strength, can be applied to a factory product. Anti fungus of the concrete using nanometric silver solution was not clear but if those specimens were aged in $CO_2$ gas for a long time it might apparent.

• 한국분말재료학회지
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• 제28권1호
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• pp.44-50
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• 2021

Zinc selenide (ZnSe) nanoparticles were synthesized in aqueous solution using glutathione (GSH) as a ligand. The influence of the ligand content, reaction temperature, and hydroxyl ion concentration (pH) on the fabrication of the ZnSe particles was investigated. The optical properties of the synthesized ZnSe particles were characterized using various analytical techniques. The nanoparticles absorbed UV-vis light in the range of 350-400 nm, which is shorter than the absorption wavelength of bulk ZnSe particles (460 nm). The lowest ligand concentration for achieving good light absorption and emission properties was 0.6 mmol. The reaction temperature had an impact on the emission properties; photoluminescence spectroscopic analysis showed that the photo-discharge characteristics were greatly enhanced at high temperatures. These discharge characteristics were also affected by the hydroxyl ion concentration in solution; at pH 13, sound emission characteristics were observed, even at a low temperature of 25℃. The manufactured nanoparticles showed excellent light absorption and emission properties, suggesting the possibility of fabricating ZnSe QDs in aqueous solutions at low temperatures.

• 전자공학회논문지 IE
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• 제44권2호
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• pp.26-31
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• 2007

카본나노튜브 전계 방출 어레이(carbon nanotube field emission array, CNT FEA)를 유리기판 상에 형성시키기 위하여 CNT 페이스트를 스크린 프린팅 후 표면처리를 수행하였다. 본 실험에서는 효과적인 표면처리 방법으로서 이온 빔을 조사(expose)시키는 방법을 연구하였다. 먼저, 유리 기판상에 감광성 CNT 페이스트를 스크린 프린팅하고 UV 후면노광 및 현상공정에 의해 선택적으로 CNT 페이스트를 남겼다. 다시 고온에서 소성후 CNT들은 바인더 성분들에 의해 문히게 된다. 본 실험에서는 소성된 CNT 페이스트의 표면상에 Ar 이온빔을 가속시켜 페이스트의 바인더(binder)를 선택적으로 제거함으로써 전계방출 특성을 향상시킬 수 있었다. 표면처리를 위한 이온 빔 가속시 이온빔의 가속에너지에 따라 특성이 크게 변화되었는데, 본 연구에서는 100 V의 낮은 가속 전압에서 가장 높은 전계방출 특성을 나타내었으며 가속 전압이 너무 높으면 바인더 성분 외에도 CNT 자체가 제거됨으로써 오히려 특정이 저하됨을 알 수 있었다.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2004년도 Asia Display / IMID 04
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• pp.518-521
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• 2004

The degradation characteristics of MgO protective layer and phosphors have been investigated in terms of the ion-induced secondary electron emission coefficient ${\gamma}$ and static margin of discharge voltages, respectively, in this experiment. The ion-induced secondary electron emission coefficients ${\gamma}$ for the degraded MgO protective layer and phosphors have been studied by ${\gamma}$ -focused ion beam system. The energy of Ne+ ions used is from 80 eV to 200 eV in this experiment. The degraded MgO and phosphor layers are found to have higher ${\gamma}$ than that of normal ones without degradations or aged one. Also, the static margin of discharge voltages for test panels with degraded MgO protective layer and phosphors been found to be seriously decreased in comparison with those of normal ones without degradations.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2006년도 6th International Meeting on Information Display
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• pp.877-881
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• 2006

We obtained sputtering yields for the MgO, $MgAl_2O_4$ and $MgAl_2O_4/MgO$ films using the FIB system. $MgAl_2O_4/MgO$ protective layers have been found to have less $24^{\sim}^30%$ sputtering yield values from 0.24 atoms/ion up to 0.36 atoms/ion than MgO layers with the values from 0.36 atoms/ion up to 0.45 atoms/ion for irradiated $Ga^+$ ion beam whose energies ranged from 10 keV to 14 keV. And $MgAl_2O_4$ layers have been found to have lowest sputtering yield values from 0.88 up to 0.11. It is also found that $MgAl_2O_4/MgO$ and MgO have secondary electron emission $coefficient({\gamma})$ values from 0.09 up to 0.12 for $Ne^+$ ion whose energies ranged from 50 eV to 200 eV.

• 한국전기전자재료학회논문지
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• 제20권7호
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• pp.615-619
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• 2007

MgO layer plays an important role for plasma display panels (PDPs). In this experiment, ion beam assisted deposition (IBAD) methode was uesed to deposit a MgO thin film and the assisting oxygen ion beam energy was varied from 100 eV to 500 eV. In order to investigate the relationship between the secondary electron emission and the defect levels of the MgO layer, we measured the cathodoluminescence (CL) spectra of the MgO thin films, and we analyzed the CL peak intensity and peak transition. The results showed that the assisting ion beam energy played an important role in the peak intensity and the peak transition of the CL spectrum. The properties of MgO thin film were also analyzed using XRD and SEM, these results showed the assisting ion beam energy had direct effect on characteristics of MgO thin film.

• E2M - 전기 전자와 첨단 소재
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• 제10권8호
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• pp.763-769
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• 1997

In this study we have synthesized Zno:Eu phosphors under various sintering atmospheres and temperatures. The analysis of X-ray diffractometer measurement indicates that for Zno:EuCl$_3$ phosphors sintered in air and vacuum 뗘 exists in the host lattice as Eu$_2$O$_3$and EuOCl respectively. From the photoluminescence for the phosphors sintered in vacuum Eu removes the broad-band emission of the ZnO host consequently isolating the red emission due to Eu$^{3+}$ ion and improves the color purity of red emission. The photoluminescence excitation and time resolving spectrum measurements suggest that energy-transfer process occurres from the self-activated defect center in ZnO host the Eu$^{3+}$ ion which exist in the host lattice in the form of EuOCl.

• 천문학논총
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• 제10권1호
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• pp.127-134
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• 1995

Recent discovery of an Io-related feature in Jupiter's auroral regions prompted us to search for an or multiplet at $1304{\AA}$ in IUE aurora spectra. In three independent IUE spectra taken on January 18, 1981, we found an emission structure at $1304{\AA}$, with a signal-to-noise of about three. If the structure is due to the OI emission, then it is a direct evidence of oxygen ion precipitation, which may originate from Io and Io torus. The emission rates of the $H_2$ band systems and the or multiplet are about 50 kR and 150 R, respectively. We have constructed high resolution model spectra with the estimated emission rates of $H_2$, OI and SI for the Goddard High Resolution Spectrograph (GHRS) onboard the Hubble Space Telescope. The model spectra clearly show the or and SI mulitplets separated from crowded $H_2$ Lyman and Werner band lines, and therefore it is promising to detect the OI and SI multiplets with the GHRS. Given the possibility that the lo-related feature may be caused by ion precipitations from the Io flux tube, it is likely that the OI emission may be detected in the footprint area of the IO flux tube.