• Proceedings of the Korean Vacuum Society Conference
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• 2011.02a
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• pp.68-68
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• 2011

As feature size is smaller, new technology are needed in semiconductor factory such as gap-fill technology for sub 100nm, development of ALD equipment for Cu barrier/seed, oxide trench etcher technology for 25 nm and beyond, development of high throughput Cu CMP equipment for 30nm and development of poly etcher for 25 nm and so on. We are focus on gap-fill technology for sub-30nm. There are many problems, which are leaning, over-hang, void, micro-pore, delaminate, thickness limitation, squeeze-in, squeeze-out and thinning phenomenon in sub-30 nm gap fill. New gap-fill processes, which are viscous oxide-SOD (spin on dielectric), O3-TEOS, NF3 Based HDP and Flowable oxide have been attempting to overcome these problems. Some groups investigated SOD process. Because gap-fill performance of SOD is best and process parameter is simple. Nevertheless these advantages, SOD processes have some problems. First, material cost is high. Second, density of SOD is too low. Therefore annealing and curing process certainly necessary to get hard density film. On the other hand, film density by Flowable oxide process is higher than film density by SOD process. Therefore, we are focus on Flowable oxide. In this work, dielectric film were deposited by PECVD with TSA(Trisilylamine - N(SiH3)3) and NH3. To get flow-ability, the effect of plasma treatment was investigated as function of O2 plasma power. QMS (quadruple mass spectrometry) and FTIR was used to analysis mechanism. Gap-filling performance and flow ability was confirmed by various patterns.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2018.06a
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• pp.110-110
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• 2018

여러 니켈합금 중 인코넬 600은 원전 가압경수로(PWR)의 튜브 재료로 널리 사용되는 재료이다. 스테인리스강과 비교하여 우수한 내식성과 기계적 특성으로 인해 화학설비, 발전설비, 그리고 해양설비 등과 같은 여러 산업분야에서도 널리 사용되고 있다. 그러나 가압경수로용 증기 발생기의 튜브 재료와 같은 특수 환경에서 예민화에 따른 입계부식 및 입계응력부식 등의 문제가 흔히 보고되고 있다. 이러한 내구성 문제는 설비 및 장비의 수명, 내구성 그리고 안정성 등의 치명적인 영향을 미친다. 따라서 용접, 열처리, 그리고 가공과정에서 발생하는 Inconel 600의 예민화 및 입계부식에 관한 연구가 활발히 진행되고 있다. 그러나 100시간 이상 장시간 열화된 시편에 대한 예민화 연구는 전무한 실정이다. 본 연구에서는 장시간 열화된 Inconel 600의 예민화를 평가하기 위해 최대 1,000시간까지 열화를 실시하였으며, 이에 대한 평가방법으로 Double-Loop Electrochemical Potentiokinetic Reactivation(DL-EPR) 시험법을 적용하였다. 본 실험에서 사용된 인코넬 600의 화학성분(wt, %)은 0.01 C, 0.05 Si, 0.14 Mn, 15.3 Cr, 0.5 Cu, 0.015 S, 그리고 나머지는 Ni 이다. 예민화 평가를 위한 등온 열화는 전기열처리로를 이용하여, $550^{\circ}C$와 $650^{\circ}C$에서 최대 1000시간까지 실시하였다. 열화에 따른 미세조직 변화는 scanning electron microscope와 energy dispersive x-ray spectroscopy를 이용하여 실시하였다. DL-EPR 실험은 $25^{\circ}C$의 0.1M $H_2SO_4$ + 0.001M KSCN(potasium thiocyanate) 수용액 하에서 실시하였으며, 분극은 OCP로부터 600 mV(SSE vs.)까지 1.67mV/s 주사속도로 forward scan을 실시 후, 동일한 속도로 OCP까지 reverse scan을 실시하였다. Degree Of Sensitization(DOS)값은 anodic scan peak($I_a$) 값과 reverse scan peak($I_r$) 값의 비로 산출하였다. $$i.e.\;DOS=I_r/I_a{\times}100$$. 그 결과, 온도 변수에 따른 Inconel 600강의 예민화 거동은 서로 상이한 경향을 나타내었다. $550^{\circ}C$의 경우, 열화가 진행됨에 따라 DOS값은 급격하게 증가하는 경향을 나타냈다. 반면, $650^{\circ}C$에서는 일정시간 이후부터 Cr 확산 현상에 의한 탈 예민화 현상이 관찰되었다.

• Resources Recycling
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• v.15 no.6 s.74
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• pp.16-24
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• 2006

In this study, the neutralization and dechlorination process of MWI(Municipal Waste Incinerator) fly ash with $H_2SO_4$ are investigated to recover HCI, which is delivered from the reaction of chloride in the ash and sulfuric acid. The coarse crystalline gypsum and fine impurity containing heavy metal are also separated by 500# wet screening followed by recrystallization of the dechlorinated ash mainly made of $CaSO_4$. As a results, Using 100g MWI fly ash and 85g cone. sulfuric acid as raw material, 52.6g hydrochloric acid with 35% assay and 116.9g crystalline gypsum with 98% or more assay are recovered. In this process, 7.85g fine impurity containing heavy metal and 2.65g coarse impurity are also separated.

• Journal of the Korean Vacuum Society
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• v.18 no.1
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• pp.73-78
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• 2009

Zinc Oxide (ZnO) nanorods arrays were deposited on ZnO buffered p-Si(100) substrates by hydrothermal method. The ZnO buffer layer with a thickness of 30 nm was deposited by metal oxide chemical vapor deposition at $500^{\circ}C$. The structural and optical properties of ZnO nanorods arrays controlled by precursor concentrations from 0.06 to 0.5 M were studied by FE-SEM(field emission scanning electron microscopy), XRD(X-ray diffraction), and PL(photoluminescence), respectively. It was found that the structural and optical properties of ZnO nanorods arrays are changed significantly with increase of precursor concentration. The sizes of diameter and length of nanorods were increased as the concentration increase, and good optical property was shown with the concentration of 0.3 M.

• The Korean Journal of Food And Nutrition
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• v.32 no.2
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• pp.89-97
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• 2019

In this paper, quality properties and antioxidant capacity of cooked black carrot has been studied. Five different cooking methods have been applied: microwave (45 sec), boiling ($100^{\circ}C$, 14 min), steaming ($100^{\circ}C$, 20 min), sous vide ($75^{\circ}C$, 80 min), sous-vide ($95^{\circ}C$, 30 min). The color value was slightly different (p<0.05), the boiling method was the highest in L-value and Sous vide $75^{\circ}C$ method was the lowest. The steaming method indicated the highest a-value at 5.50. The b-value was significantly different between the samples (p<0.05). The microwave method was the highest at 3.49 while the sous vide $95^{\circ}C$ method was the lowest at -0.34. No significant difference was observed between the samples when only the moisture content results were considered. The highest pH was observed in samples cooked using the boiling method. The softening (%) was higher when the cooking water was in contact with samples and it was dependent on the temperatures. In addition, this study shows that not only temperature but also cooking time and cooking media are very crucial in the preparation and cooking of black carrot to prevent the loss of the antioxidant compound. In conclusion, the comparison of the quality characteristics and antioxidant properties of black carrots indicated that the most appropriate cooking method is sous-vide method.

• Clean Technology
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• v.6 no.1
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• pp.61-69
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• 2000

In this study, generation process and properties of inorganic industrial waste which can be used in cement industry were investigated. The scheme of recycling to use the selected waste as raw materials, mineralizer and flux, admixture and raw materials for special cement was decided and then various experiments were carried out. The experimental results were as follows ; In the use of industrial waste as raw materials, ferrous materials could be substituted by Cu-slag, Zn-slag, electric arc furnace or convertor furnace slag etc., and a siliceous material could be substituted by sand from cast-iron industry. By-products from sugar or fertilizer industry, which has $CaF_2$ as the main component, and jarosite from Zn refinery enabled clinker phases to be formed at lower temperature by $100{\sim}150^{\circ}C$. Adding Cu slag and STS sludge in proper proportion to cement improved properties of cement. Fly ash and limestone powder as admixture had the same effect on cement. As a raw material for special cement, aluminium waste sludge could be used in making ultra early strength cement, which had the compressive strength of $300kg/cm^2$ within 2hours. And two different ashes from municipal incinerator could be raw materials of the cement which was mainly composed of $C_3S$ and $C_{11}A_7{\cdot}CaCl_2$ as clinker phases.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.9
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• pp.1295-1303
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• 2015

Berry fruits are rich in phytochemicals, including polyphenols, anthocyanins, phenolic acids, and organic acids, which are known to have beneficial effects on health. The aim of this study was to investigate chemical composition, functional constituents, and antioxidant activities of mulberry, black raspberry, raspberry, and blueberry cultivated in Korea. Acidity of the four berries ranged from 0.26% to 1.10%, and pH ranged from 3.3 to 5.2. Total mineral contents of the four berries ranged from 92.9 to 256.0 mg/100 g. Among the berries, mulberry contained the most abundant total free sugars, and glucose and fructose were the major sugars in the berries. Mulberry contained more than three times as much ${\gamma}-aminobutyric$ acid as the content of the other berries. Blueberry contained more free phenolic acid than the other berries. Especially, chlorogenic acids were the major free phenolic acids in blueberry. Black raspberry had the highest amount of polyphenols, anthocyanins, and flavonoids among the berries and showed the highest antioxidant activity.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.11 no.2
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• pp.49-55
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• 2001

ZnO films were fabricated on p-type Si(100) wafer ITO glass and quartz glass by the sol-gel process using zinc acetate dihydrate as starting material. A homogeneous and stable solution was prepared by dissolving the zinc acetate dihydrate in a solution of 2-methoxyethanol and monoethanolamine (MEA). ZnO films were deposited by spin-coating at 2800 rpm for 25 s and were dried on a hot plate at $250^{\circ}C$ for 10 min. Crystallization of the films was carried out at $400^{\circ}C$~$800^{\circ}C$ for 1 h in air. X-ray diffraction (XRD) analysis, scanning electron microscopy (SEM), UV-vis transmittance spectroscopy, FTIR transmittance spectroscopy and Photoluminescence (PL) spectroscopy measurements have been used to study the structural and optical properties of the films. ZnO films highly oriented along the (002)plane were obtained. In all cases the films were found to be transparent (above 70%) in visible range with a sharp absorption edge at wavelengths of about 380nm, which is very close to the intrinsic band-gap of ZnO(3.2 eV). The low temperature band-edge photoluminescence revealed a complicated multi-line structure in terms of bound exciton complexes and the phonon replicas.

• Journal of the Korean Vacuum Society
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• v.16 no.4
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• pp.262-266
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• 2007

Polycrystalline $Mn_xFe_{3-x}O_4$ thin films were synthesized on Si(100) substrates using sol-gel method and the effects of Mn substitution on the structural, magnetic, and magnetotransport properties were analyzed. X-ray diffraction revealed that cubic structure is maintained up to x = 1.78 with increasing lattice constant for increasing x. Such increase of the lattice constant is attributable to the substitution of $Mn^{2+}$ (with larger ionic radius) ions into tetrahedral $Fe^{3+}$(with smaller ionic radius) sites. VSM measurements revealed that $M_s$ does not vary significantly with x, qualitatively explainable by comparing spin magnetic moments of Mn and Fe ions. On the other hand, $H_c$ was found to decrease with increasing x, attributable to the decrease of magnetic anisotropy due to the decrease of $Fe^{2+}$ density through $Mn^{2+}$ substitution. Magnetoresistance (MR) of the $Mn_xFe_{3-x}O_4$ films was found to decrease with increasing x. Analysis of the MR data in comparison with the VSM results gives an indication of the tunneling of spin-polarized carriers through the grain boundaries of the polycrystalline samples at low external field and spin-flip of the carriers at high external field.

• Korean Journal of Soil Science and Fertilizer
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• v.40 no.6
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• pp.482-487
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• 2007

This study was conducted to investigate the effect of long-term continuous application of fertilizers for rice cultivation. Changes of physical and chemical properties of paddy soil and the rice yield by continuous application of NPK fertilizers, ammonium sulphate, and urea over fifty years, from 1954 to 2003, were investigated. The rice yield index of each treatment were 100 of NPK plots, 84 of ammonium sulphate plots, 81 of urea plots, and 62 of no fertilizer plots. The variance of yield was large according to the quality of irrigation water. Nutrient uptakes by rice plants in ammonium sulphate and urea plots were significantly smaller than those in NPK plots; 86 and 75% in T-N, 79 and 82% in $P_2O_5$, 64 and 58% in $K_2O$, and 94 and 90% in $SiO_2$, respectively. Bulk density of soil in NPK plots significantly decreased compared to those in no fertilizer, ammonium sulphate, and urea plots, whereas CEC in NPK plots increased compared to other plots. Soil pHs of all plots were higher than that before experiment which was 5.2; 6.0 in no fertilizer, 5.9 in urea and NPK, and 5.4 in ammonium sulphate plots. The available phosphate in soil increased by $2.5mg\;kg^{-1}\;yr^{-1}$ when $70kg\;ha^{-1}$ of P fertilizer applied for rice cultivation, and decreased by $1.8mg\;kg^{-1}\;yr^{-1}$ when no P fertilizer applied.