• Proceedings of the Korean Vacuum Society Conference
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• 2011.02a
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• pp.118-118
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• 2011

The Nano-Floating Gate Memory(NFGM) devices with ZnO:Cu thin film embedded in Al2O3 and AlOx-SAOL were fabricated and the electrical characteristics were evaluated. To further improve the scaling and to increase the program/erase speed, the high-k dielectric with a large barrier height such as Al2O3 can also act alternatively as a blocking layer for high-speed flash memory device application. The Al2O3 layer and AlOx-SAOL were deposited by MLD system and ZnO:Cu films were deposited by ALD system. The tunneling layer which is consisted of AlOx-SAOL were sequentially deposited at $100^{\circ}C$. The floating gate is consisted of ZnO films, which are doped with copper. The floating gate of ZnO:Cu films was used for charge trap. The same as tunneling layer, floating gate were sequentially deposited at $100^{\circ}C$. By using ALD process, we could control the proportion of Cu doping in charge trap layer and observe the memory characteristic of Cu doping ratio. Also, we could control and observe the memory property which is followed by tunneling layer thickness. The thickness of ZnO:Cu films was measured by Transmission Electron Microscopy. XPS analysis was performed to determine the composition of the ZnO:Cu film deposited by ALD process. A significant threshold voltage shift of fabricated floating gate memory devices was obtained due to the charging effects of ZnO:Cu films and the memory windows was about 13V. The feasibility of ZnO:Cu films deposited between Al2O3 and AlOx-SAOL for NFGM device application was also showed. We applied our ZnO:Cu memory to thin film transistor and evaluate the electrical property. The structure of our memory thin film transistor is consisted of all organic-inorganic hybrid structure. Then, we expect that our film could be applied to high-performance flexible device.----못찾겠음......

• Corrosion Science and Technology
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• v.8 no.1
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• pp.40-43
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• 2009

We investigated the corrosion resistance of Zn and Cu coated steel pipes as a substitute for Cu pipe in an air-conditioner system. In addition, the galvanic corrosion tendency between two dissimilar metal parts was studied. The corrosion resistance of the Cu electroplated steel was similar to that of Cu, while the corrosion rate of the Zn electro- galvanized and the galvalume (Zn-55 % Al) coated steels was much higher and not suitable for Cu substitute in artificial sea water and acidic rain environments. Furthermore, the galvanic difference between Cu electroplated steel and Cu was so small that the Cu coated steel pipe can be used as a substitute for Cu pipe in an air-conditioner system.

• BMB Reports
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• v.32 no.5
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• pp.440-444
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• 1999

Membrane lipid peroxidation processes yield reactive aldehydes that may react with copper,zinc superoxide dismutase (Cu,Zn SOD), one of the key antioxidant enzymes against oxidative stress. We investigated this possibility and found that exposing Cu,Zn SOD to malondialdehyde (MDA) or 4-hydroxynonenal (HNE) caused the loss of dismutase activity, cross-linking of peptides, and an increase in protein oxidation, reflected by the increased level of carbonyl groups. When Cu,Zn SOD that had been exposed to MDA or HNE was subsequently analyzed by amino acid analysis, histidine content was found to be significantly lost. Both MDA-and HNE-treated Cu,Zn SOD were resistant to proteolysis, which may imply that damaged proteins exist in vivo for a longer period of time than the native enzyme. The lipid peroxidation-mediated damage to Cu,Zn SOD may result in the perturbation of cellular antioxidant defense mechanisms, and subsequently lead to a pro-oxidant condition.

• Economic and Environmental Geology
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• v.30 no.2
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• pp.117-122
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• 1997

Soils collected from pusan metropolitan city were analysed for Cu, Pb, Zn, Cd, Mn to determine their dispersion patterns, mode of occurrences and to investigate the pollution level of heavy metals by urbanization. Element couples of Zn-Cu and Pb-Cd showed good correlation respectively and pollution sources of Zn-Cu, and Pb-Cd were similar. Pb was highly enhanced in dense traffic areas. Soil chemistry around mineralized areas originating from basic host rocks are characterized by high content of Pb, Zn, Cu, Cd, Mn and As.

• Bulletin of the Korean Chemical Society
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• v.23 no.12
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• pp.1765-1768
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• 2002

The isotherms of CO adsorption on the Cu/ZnO sample treated with with hydrogen and methanol are investigated. The heats of adsorption of CO on the Cu/ZnO treated with hydrogen at 723K for 3 h are in the range from 25.7 kJ/mol at $\theta=0.8$ to 59.8 at $\theta=0.1$, while those on the Cu/ZnO sample treated with methanol at 523 K for 3 h are in the range 30.3 kJ/mol at $\theta=0.8$ to 99.8kJ/mol at $\theta=0.1.$ The Cu/ZnO samples treated with hydrogen do. The heats of adsorption at q=0.1 increase with the methanol treatment time within 30 min and leveled off afterwards.

• Proceedings of the International Microelectronics And Packaging Society Conference
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• 2002.05a
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• pp.165-168
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• 2002

본 연구에서는 칩인덕터 코어 소재로 사용되는 (NiCuZn)-ferrite를 습식합성법을 이용하여 나노크기의 초미세 분말을 합성하였으며, 합성된 (ZiCuZn)-ferrite 의 제조공정 및 전파기적 특성에 관하여 고찰하였다. 조성은 (N $i_{0.4-x}$C $u_{x}$Z $n_{0.6}$)$_{1+w}$ (F $e_2$ $O_4$)$_{1-w}$에서 x의 값을 0.05~0.25 범위로 변화시켰으며, w 값은 0.03으로 고정하였다. 소결은 8$50^{\circ}C$에서 9$50^{\circ}C$의 범위에서 진행하였다. 나노크기의(NiCuZn)-ferrite를 사용함으로서 시약급 원료로 제조된 것보다 소결온도를 낮출 수 있었고, 밀도가 높은 페라이트 소결체를 얻을 수 있었다. 또한 초투자율, 품질계수 등 전자기적 특성이 우수하게 나타났다. 그 밖에 습식합성법으로 합성한 (NiCuZn)-ferrite 의 결정성, 미세구조 등을 XRD, SEM 을 이용하여 고찰하였다.하였다.다.

• Journal of the Korean institute of surface engineering
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• v.45 no.5
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• pp.188-192
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• 2012

The hetero junction on dielectrics and ferrite for LTCC was prepared by using NiCuZn ferrite. The shrinkage behaviour of ferrite tapes in combination with a dielectric tape was investigated. The characteristics of NiCuZn ferrite were investigated using XRD (X-ray diffractometer), Dilatometer, FE-SEM (Field emission scanning electron microscope), EDS (Energy dispersive spectrometer). NiCuZn ferrite calcined at $700^{\circ}C$ had a good apparent density and initial permeability of magnetic properties. The shrinkage rate of the NCZF700 ferrite and dielectric material was similar. The multilayer revealed dense, uniform morphologies with excellent interface quality. Diffusion of hetero junction such as dielectric and ferrite was not occuring at $900^{\circ}C$.

• Journal of the Korean Magnetics Society
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• v.5 no.5
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• pp.556-560
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• 1995

The absorption properties of Cu-Zn ferrite/rubber composite microwave absorbers with PZT(Lead Zirconate Titanate) additive were evaluated. The composite specimens have prepared by molding and curing the mixture of matrix rubber and Cu-Zn ferrite powders which are synthesized by the coprecipitation method using Fe Cl/sub 3/ .center dot. 6H/sub 2/O, CuCl/sub 2/ .center dot. 2H/sub 2/O and Zn Cl/sub 2/ as a starting raw materials. PZT is used as another filler particles to adjust the material constants of Cu-Zn ferrite/rubber composite specimens. We have found that the material constants of specimens could be controlled by various PZT mixing ratio. On the Cu-Zn ferrite/rubber composite specimens with PZT 10[wt%] additive, the reflection losses were larger than 30[dB] in the frequency range from 2.72 to 4.4[GHz]' by adjusing the thickness.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.35 no.6
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• pp.562-567
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• 2022

Novel self-illuminated smart windows were fabricated consisting of Cu-doped ZnS (ZnS:Cu) powder and polymer-dispersed liquid crystal (PDLC). This smart window shows not only switchable transparency but also self-illumination without any attachable luminous body. Its electro-optical characteristics, transmittance, and luminance were investigated in relation to various applied voltages and composition ratios. The optical transmittance and luminous intensity increased with increasing applied voltages. However, the optical transmittance decreased with increasing ZnS:Cu powder content. One of the self-illuminated smart windows, which was fabricated with 9 wt% of ZnS:Cu, achieved the optical transmittance of 60.5% (at 550 nm) and the luminance of 11.0 cd/m² at 100 V. This smart window could be used as a normal switchable smart window in daytime and light-emitting signage at night.

• Korean Journal of Soil Science and Fertilizer
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• v.11 no.2
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• pp.119-126
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• 1979

Rice seeds, suweon 264, were germinated under 5 levels of toxic heavy metals, Cd(0, 0.05, 0.5, 5, 20ppm), Cu(0, 0.05, 0.5, 5, 20, ppm), Cr(0, 0.5, 1, 5, 10ppm), Ni(0, 0.5, 1, 5, 10ppm), Co(0, 0.5, 1, 5, 10ppm), Zn(0, 0.5, 5, 20, 40, ppm), Pb(0, 0.5, 5, 20, 40ppm) and Mn(0, 1, 10, 25, 50, ppm) in culture solution, and then grown with supplying culture solution contained respective concentrations. Germination and growth response to the toxic heavy metals were studied. Results obtained are as follows : 1) The germination injury of rice seeds by excess concentration of toxic heave metal in culture solution occured in Cd and Cu; below 0.05 ppm, Ni; below 0.5 ppm, Mn; below 1.0 ppm, Co and Cr; 0.5-1.0 ppm, and 0.5-5 ppm, Zn and Pb. Thereby, in the order of degrees of the elements toxicity to germination, they were arranged as follows : Cd>Cu>Ni>Co>Cr>Mn>Zn$$\geq_-$$Pb. 2) Toxic heavy metal concentrations in culture solution, which result in decreasing dry weight due to the injury of excess concentration of treated elements, were Cd: below 0.05 ppm, Ni, Cr and Co; below 0.5 ppm, Cu and Zn; 0.5-5 ppm, Pb; 5-20 ppm and Mn; 10-25 ppm. The order was Ni>Cd>Cr>Co>Cu$$\geq_-$$Zn>Pb>Mn. 3) The critical contents of Cd, Ni, Pb, Cu, Zn, Mn, and Co in dry matter, Which result in decreasing dry weight, were considered to be 0.05-15.5, 1.50-25.0, 24.0-28.0, 26.5-62.5, 470-645.0, 231.0-500.0 and below 15.0 ppm, respectively. 4) The contents of Cr, Co, Cd, Pb, Ni, Cu and Zn in dry matter by 0.5 ppm treatment concentration of each heavy metals was trace, 15.0, 17.5, 24.0, 25.0, 84.5 and 470.0 ppm, respectively. Thereby, in the order of each element to uptaked by rice seedlings, they were arranged as follow; Zn>Cu>Ni>Pb>Cd>Co>Cr. 5) The hazardous concentrations of root activity by toxic heavy metals in culture solution were Cd; below 0.05, Cu; 0.05-0.5, Cr; below 0.5, Ni; 0.5-1.0, Co; 0.5-1.0, Zn; above 0.5, Pb; 0.5-5.0 and Mn; 1.0-10.0 ppm. The hazardous degree of root activity by toxic heave metals was in the order of Cd>Cu>Cr>Zn>Ni>Co>Pb>Mn.