• Title/Summary/Keyword: ${\omega}-6/{\omega}-3$ ratio

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a-Si:H TFT Using Ferroelectrics as a Gate Insulator (강유전체를 게이트 절연층으로 한 수소화 된 비정질실리콘 박막 트랜지스터)

  • 허창우;윤호군;류광렬
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2003.10a
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    • pp.537-541
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    • 2003
  • The a-Si:H TFTs using ferroelectric of SrTiO$_3$, as a gate insulator is fabricated on glass. Dielectric characteristics of ferroelectric is better than SiO$_2$, SiN. Ferroelectric increases ON-current, decreases threshold voltage of TFT and also breakdown characteristics. The a-Si:H deposited by PECVD shows absorption band peaks at wavenumber 2,000 $cm^{-1}$ /, 635 $cm^{-1}$ / and 876 $cm^{-1}$ / according to FTIR measurement. Wavenumber 2,000 $cm^{-1}$ /, 635 $cm^{-1}$ / are caused by stretching and rocking mode SiH1. The wavenumber of weaker band, 876 $cm^{-1}$ / is due to SiH$_2$ vibration mode. The a-SiN:H has optical bandgap of 2.61 eV, refractive index of 1.8 - 2.0 and resistivity of 10$^{11}$ - 10$^{15}$ aim respectively. Insulating characteristics of ferroelectric is excellent because dielectric constant of ferroelectric is about 60 - 100 and breakdown strength is over 1 MV/cm. TFT using ferroelectric has channel length of 8 - 20 $\mu$m and channel width of 80 - 200 $\mu$m. And it shows drain current of 3 $\mu$A at 20 gate voltages, Ion/Ioff ratio of 10$^{5}$ - 10$^{6}$ and Vth of 4 - 5 volts.

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Characteristics of MOCVD Cobalt on ALD Tantalum Nitride Layer Using $H_2/NH_3$ Gas as a Reactant

  • Park, Jae-Hyeong;Han, Dong-Seok;Mun, Dae-Yong;Yun, Don-Gyu;Park, Jong-Wan
    • Proceedings of the Korean Vacuum Society Conference
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    • 2012.02a
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    • pp.377-377
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    • 2012
  • Microprocessor technology now relies on copper for most of its electrical interconnections. Because of the high diffusivity of copper, Atomic layer deposition (ALD) $TaN_x$ is used as a diffusion barrier to prevent copper diffusion into the Si or $SiO_2$. Another problem with copper is that it has weak adhesion to most materials. Strong adhesion to copper is an essential characteristic for the new barrier layer because copper films prepared by electroplating peel off easily in the damascene process. Thus adhesion-enhancing layer of cobalt is placed between the $TaN_x$ and the copper. Because, cobalt has strong adhesion to the copper layer and possible seedless electro-plating of copper. Until now, metal film has generally been deposited by physical vapor deposition. However, one draw-back of this method is poor step coverage in applications of ultralarge-scale integration metallization technology. Metal organic chemical vapor deposition (MOCVD) is a good approach to address this problem. In addition, the MOCVD method has several advantages, such as conformal coverage, uniform deposition over large substrate areas and less substrate damage. For this reasons, cobalt films have been studied using MOCVD and various metal-organic precursors. In this study, we used $C_{12}H_{10}O_6(Co)_2$ (dicobalt hexacarbonyl tert-butylacetylene, CCTBA) as a cobalt precursor because of its high vapor pressure and volatility, a liquid state and its excellent thermal stability under normal conditions. Furthermore, the cobalt film was also deposited at various $H_2/NH_3$ gas ratio(1, 1:1,2,6,8) producing pure cobalt thin films with excellent conformality. Compared to MOCVD cobalt using $H_2$ gas as a reactant, the cobalt thin film deposited by MOCVD using $H_2$ with $NH_3$ showed a low roughness, a low resistivity, and a low carbon impurity. It was found that Co/$TaN_x$ film can achieve a low resistivity of $90{\mu}{\Omega}-cm$, a low root-mean-square roughness of 0.97 nm at a growth temperature of $150^{\circ}C$ and a low carbon impurity of 4~6% carbon concentration.

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Chemical and Bacteriological Water Qualify of the Sonakdong River (서낙동강 강수의 화학적${\cdot}$세균학적 수질)

  • KIM Yong Gwan
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.19 no.4
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    • pp.347-355
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    • 1986
  • The Sonakdong river is very important water source not only for agricultural water of Kimhae field but also for fishery water. Recently the middle and lower areas of the river have the tendency to be heavily contaminated by domestic sewage and agricultural chemicals. Fifty six water samples were collected from 8 stations from July to December in 1985 for the experiment (Fig. 1). To evaluate the water quality, pH, water temperature, electrical conductivity, chloride ion, nutrients ($NO^{-}_{2}-N,\;NO^{-}_{3}-N,\;NH^{+}_{4}-N,\;PO^{3-}_{4}-P,\;SiO_2-Si$), total coliform, fecal coliform, and fecal streptococcus were determined. Range and mean value of the samples were as follows; pH $6.3{\sim}9.4$, 7.91; water temperature $6.1{\sim}34.8^{\circ}C,\;23.88^{\circ}C$; electrical conductivity (from St. A to G) $1.575{\times}10^2{\sim}30.50{\times}10^2{\mu}{\mho}/cm,\;6.57{\times}10^2{\mu}{\mho}/cm$; chloride ion $23.5{\sim}14,300mg/l$, 770.0mg/l; nitrite-nitrogen $0.007{\sim}0.110mg/l$, 0.053mg/l; nitrate-nitrogen $0.001{\sim}1.638mg/l$, 0.649 mg/l; ammonia-nitrogen $0.017{\sim}4.200mg/l$, 0.497mg/l; phosphate-phoshorus $0.011{\sim}0.281mg/l$, 0.086mg/l; and silicate-silicious $2.4{\sim}6.5mg/l$, 4.43mg/l. Electrical conductivity and chloride ion of the station F(Chomanpo) were $2.676{\times}10^2{\mu}{\Omega}cm$ and 123.99mg/l which were lower than those of others. Among the analyzed nutrients, silicate-silicious concentration was the highest through all the samples. The bacterial density of the samples ranged $36{\sim}110,000/100ml$ for total coliform, $15{\sim}46,000/100ml$ for fecal coliform and $3.6{\sim}15,000/100ml$ for fecal streptococcus. The range and the mean of the TC/FC ratio were $3.0{\sim}9.6$, 5.51 and those of the FC/FS ratio were $1.1{\sim}9.2$, 6.19, respectively. On the other hand, fecal coliform was not detected in about $78\%$ of the water samples examined. Composition of coliform was $52\%$ Escherichia coli group, $3\%$ Citrobacter freundii group, $13\%$ Enterobacter aerogenes group and $31\%$ others.

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Serum Concentration of Major Minerals, Trace Elements, Lipids and Fatty Acids Composition Related to Whole Cow's Milk Feeding in Infancy & Young Childhood (생우유 과량섭취와 관련된 영유아의 혈청 무기질과 미량원소 함량 및 지질조성)

  • 안홍석;배현숙;박성혜;정은정;오경환
    • Korean Journal of Community Nutrition
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    • v.2 no.4
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    • pp.477-485
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    • 1997
  • This study was conducted to determine the effect of large amounts of whole cow's milk intake on serum levels of minerals and lipids. Subjects were normal infants who were brought to the pediatric hospital for vaccination at the age of 7-26 months after birth, living in Eumsung-Choongbuk area. The serum concentrations of the imnerals(calcium, phosphorus, magnesium, iron, zinc and copper), lipids and fatty acids composition were analyzed in 38 infants which consumed large amount of whole cow's milk(over 700ml/day). The results obtained are summarized as follows : 1) The mean levels of calcium, phosphorus and magnesium in the serum of the total subjects were 7.56$\pm$0.51mg/dl, 11.12$\pm$0.72mg/dl and 1.62$\pm$0.13mg/dl respectively. The serum concentrations of iron, zinc and copper in total subjects averaged 72.42$\pm$1.62$\mu\textrm{g}$/dl, 76.29$\pm$3. 62$\mu\textrm{g}$/dl and 86.44$\pm$2.98$\mu\textrm{g}$/dl respectively. 2) The mean serum concentrations of triglyceride, total cholesterol, HDL and LDL in the total number of subjects were 96.84$\pm$9.22mg/dl, 133.45$\pm$6.30mg/dl, 32.79$\pm$1.77mg/dl and 81.29$\pm$4.81mg/dl respectively. 3) The average percentages of SFA, MUFA and PUFA inth total serum fatty acids were 38.98$\pm$2.42$\%$, 25.82$\pm$0.98$\%$ and 37.30$\pm$1.09$\%$ respectively and the mean$w6/w3$fatty acids ratio was 13.48. In general, the levels of serum minerals and $\omega$3 fatty acid composition in the subjects of this study, who were whole cow's milk fed infants were lower than those reported in breast milk or formula fed infants. Therefore, the intake of large amount of whole cow's milk in the weani ng period should be controlled and adequate for the infant's nutritional status. (Korean J Community 2(4) : 477-485, 1997)

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Electrical Properties of Eco-Friendly RuO2-Based Thick-Film Resistors Containing CaO-ZnO-B2O3-Al2O3-SiO2 System Glass for AlN Substrate (Electrical Properties of Eco-Friendly RuO2-Based Thick-Film Resistors Containing CaO-ZnO-B2O3-Al2O3-SiO2 계 유리가 적용된 질화알루미늄 기판용 RuO2계 친환경 후막저항의 전기적 특성 연구)

  • Kim, Min-Sik;Kim, Hyeong-Jun;Kim, Hyung-Tae;Kim, Dong-Jin;Kim, Young-Do;Ryu, Sung-Soo
    • Journal of the Korean Ceramic Society
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    • v.47 no.5
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    • pp.467-473
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    • 2010
  • The objective of this study is to prepare lead-free thick film resistor (TFR) paste compatible with AlN substrate for hybrid microelectronics. For this purpose, CaO-ZnO-$B_2O_3-Al_2O_3-SiO_2$ glass system was chosen as a sintering aid of $RuO_2$. The effects of the weight ratio of CaO to ZnO in glass composition, the glass content and the sintering temperature on the electrical properties of TFR were investigated. $RuO_2$ as a conductive and glass powder were dispersed in an organic binder to obtain printable paste and then thick-film was formed by screen printing, followed by sintering at the range between $750^{\circ}C$ and $900^{\circ}C$ for 10 min with a heating rate of $50^{\circ}C$/min in an ambient atmosphere. The addition of ZnO to glass composition and sintering at higher temperature resulted in increasing sheet resistance and decreasing temperature coefficient of resistance. Using $RuO_2$-based resistor paste containing 40 wt%glass of CaO-20.5%ZnO-25%$B_2O_3$-7%$Al_2O_3$-15%$SiO_2$ composition, it is possible to produce thick film resistor on AlN substrate with sheet resistance of $10.6\Omega/\spuare$ and the temperature coefficient of resistance of 702ppm/$^{\circ}C$ after sintering at $850^{\circ}C$.

Hydrogenated a-Si TFT Using Ferroelectrics (비정질실리콘 박막 트랜지스터)

  • Hur Chang-Wu
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.9 no.3
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    • pp.576-581
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    • 2005
  • In this paper. the a-Si:H TFT using ferroelectric of $SrTiO_3$ as a gate insulator is fabricated on glass. High k gate dielectric is required for on-current, threshold voltage and breakdown characteristics of TFT Dielectric characteristics of ferroelectric are superior to $SiO_2$ and $Si_3N_4$. Ferroelectric increases on-current and decreases threshold voltage of TFT and also ran improve breakdown characteristics.$SrTiO_4$ thin film is deposited by e-beam evaporation. Deposited films are annealed for 1 hour in N2 ambient at $150^{\circ}C\~600^{\circ}C$. Dielectric constant of ferroelectric is about 60-100 and breakdown field is about IMV/cm. In this paper, the TFT using ferroelectric consisted of double layer gate insulator to minimize the leakage current. a-SiN:H, a-Si:H (n-type a-Si:H) are deposited onto $SrTiO_3$ film to make MFNS(Metal/ferroelectric/a-SiN:H/a-Si:H) by PECVD. In this paper, TFR using ferroelectric has channel length of$8~20{\mu}m$ and channel width of $80~200{\mu}m$. And it shows that drain current is $3.4{\mu}A$at 20 gate voltage, $I_{on}/I_{off}$ is a ratio of $10^5\~10^8,\;and\;V_{th}$ is$4\~5\;volts$, respectively. In the case of TFT without having ferroelectric, it indicates that the drain current is $1.5{\mu}A$ at 20gate voltage and $V_{th}$ is $5\~6$ volts. If properties of the ferroelectric thin film are improved, the performance of TFT using this ferroelectric thin film can be advanced.

The effect of high omega-3, -6 fatty acid feeding on the free fatty acid profile and meat quality traits of pork loin (오메가-3, -6 지방산 고 함유 급이가 돼지 등심의 지방산조성과 품질특성에 미치는 영향)

  • Seol, Kuk-Hwan;Kim, Ki Hyun;Joo, Bum Jin;Kim, Jo Eun;Kim, Kwang-Sik;Kim, Young Hwa;Park, Jun Cheol;Lee, Mooha
    • Korean Journal of Agricultural Science
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    • v.41 no.3
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    • pp.213-220
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    • 2014
  • This study was conducted to evaluate the effects of high n-3 or n-6 diet on free fatty acid profile and meat quality traits of pork loin. The 20 heads of commercial $Landrace{\times}Yorkshire{\times}Duroc(LYD)$ crossbreed pigs ($90.9{\pm}2.4BWkg$) were divided into four groups by added fat and oils, such as 5% tallow (Control), 5% linseed oil (T1), 5% safflower oil (T2), and mixture of linseed oil (2.5%) + safflower oil (2.5%) (T3), then reared 4 weeks. Pork loins were taken after slaughter, then sliced in 2 cm thickness and put in low-density polyethylene (LDPE) bag for analysis. T1 showed significantly high concentration of linolenic acid ($2.35{\pm}0.21%$) (p<0.05). The total amount of saturated fatty acids (SFA), mono-unsaturated fatty acids (MUFA) and poly-unsaturated fatty acid (PUFA) was significantly high in T1 ($36.05{\pm}1.18%$), C ($22.60{\pm}2.11%$) and T2 ($47.80{\pm}1.29%$), respectively (p<0.05). However, the ratio of n-6:n-3 was significantly low in T1 ($11.57{\pm}0.90$) than that of T2 ($37.56{\pm}12.51$) (p<0.05). There was no signigicant difference in lightness, redness, pH, water holding capacity and cooking loss between treatments (p>0.05). However, the yellowness of T2 was significantly higher than others (p<0.05). From those results, it was considered that feeding high n-3 and n-6 fatty acid diet to pig enables modify fatty acid profile of pork without any side effect on meat quality.

The Effect of Weight Ratio of Carbon Source to Nitrogen Source on toe Growth and the Composition of Fatty Acid of Thraustochytrium aureum ATCC 34304 (탄소원과 질소원의 무게비가 Thraustochytrium aureum ATCC 34304의 성장 및 지방산 조성 특성에 미치는 영향)

  • Kim Won-Ho;Park Seung-Hye;Song Sang-Kyu;Bae Kyung-Dong;Hur Byung-Ki
    • KSBB Journal
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    • v.20 no.4
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    • pp.266-270
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    • 2005
  • The effect of the weight ratio of carbon source to nitrogen source on the growth and the composition change of fatty acids of Thraustochytrium aureum ATCC 34304 was investigated. The cell concentration of 5 days' culture increased and then decreased according to the increase of C/N, The ratioes for the maximum biomass were unique respectively and distributed between 1 and 4 with the initial sugar concentration in the range of 5 g/L to 25 g/L. The biomass yield, $Y_{x/s}$ decreased along with the increase of C/N, but maintained a constant value 0.35 between 10 and 20. The composition of myristic acid $(C_{14:0})$, one component of the lipid synthesized by T. aureum, was not affected with the change of C/N, but the composition of palmitic acid $(C_{16:0})$ was around $20\%$ below 4 of C/N and decreased to $15\%$ according to C/N about 4. The compositions of oleic acid $(C_{18:1})$ and linoleic acid $(C_{18:2})$ increased from 0 to $20\%\;and\;7\%$ respectively. The composition of $\gamma-linoleic$ acid $(C_{18:3})$, however, reduced from $5\%\;to\;2\%$. EPA $(C_{20:5})$ and DPA $(C_{22:5})$ showed a tendency of reduction in the weight composition according to the increase of C/N, but DHA $(C_{22:6})$ had a trend maintaining an approximately constant value, around $40\%$, irrespective of the change of C/N.

Effect of Dietary Dandelion (Taraxzcum coreanum) and Dandelion Fermented Probiotics on Productivity and Meat Quality of Broilers (민들레와 생균제의 첨가가 육계의 성장 및 체조성에 미치는 영향)

  • Oh, J.I.;Kim, G.M.;Ko, S.Y.;Bae, I.H.;Lee, S.S.;Yang, C.J.
    • Korean Journal of Poultry Science
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    • v.34 no.4
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    • pp.319-327
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    • 2007
  • This experiment was designed to evaluate effects of Dandelion (Taraxzcum coreanum) and Dandelion fermented probiotics medium on the growth performance and meat quality in broiler chicks. A total of 150 "Ross" broilers,1-day old, were assigned to 5 treatments in a completely randomized design. There were 5 replications per treatment and 6 broilers in each replication for 5 weeks. The dietary treatments included a control (Dandelion and Dandelion fermentation was not added), antibiotic (0.05 chlortetracycline was added), 1.0% Dandelion supplementation and 0.5 and 1.0% Dandelion fermented probiotics, respectively. There was no significant difference in final body weight, weight gain, feed intake, and feed conversion ratio of broilers fed diets containing antibiotics, 1.0% Dandelion supplementation and 0.5 and 1.0% Dandelion fermented probiotics. The total cholesterol, HDL and LDL in plasma and meat cholesterol content was not affected by 0.5 and 1.0% Dandelion fermented probiotics and 1.0% Dandelion supplementation (P>0.05). The oleic acid content was significantly increased in 0.5% Dandelion fermented probiotics compared to that of the control (P<0.05). As a result, Dandelion and Dandelion fermented probiotics result in the influence on decreasing cholesterol in blood, particularly when adding probiotics, oleic acid that is the important factor in taste testing of meat increases thus the quality and taste of the chicken meat could be improved with the effect.