• Proceedings of the Korean Vacuum Society Conference
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• 1998.02a
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• pp.41-41
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• 1998

Rare earth metal films have been used as a buffer layer for growing ferroelectric t thin film or a seed layer for magnetic multilayer. But when it was deposited on s semiconductor substrates for the application of magneto-optic (MO) storage media, it i is difficult to exactly measure magnetic cons떠nts due to shunting current, and so it n needs to grow metal films on insulator substrate to reduce such effect. Recently, it w was reported that ultra-thin Pt layer were epitaxially grown on A12O:J by ion beam s sputtering in 비떠 high vacuum and it can be used as a seed layer for the growth of C Co-contained magnetic multilayer. In this stu$\phi$, Pt thin film were epi떠xially grown on AI2D3 ($\alpha$)OJ) by RF magnetron s sputtering. The crystalline structure was analyzed by transmission electron microscope ( (TEM) and Rutherford Back Scattering (RBS)/Ion Channeling. In TEM study, Pt was b believed to be twinned on AI잉3($\alpha$)01) su$\pi$ace about Pt(ll1) plane.Moreover, RBS c channeling spectra showed that minimum scattering yield of Pt(111)/AI2O:J(1$\alpha$)OJ) was 4 4% and Pt(11J)/AI2D3($\alpha$)OJ) had 3-fold symmetry.

• Journal of Forest and Environmental Science
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• v.24 no.2
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• pp.89-97
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• 2008

Based on the former researches, this article studied the influence of cone harvesting of Korean pine on the regeneration of Korean pine trees and the life of animals in Mt. Changbai Nature Reserve. When the cone matures, scales of the cone do not open so the seeds can not be released automatically. And the seeds, if left inside, are hard to germinate and can not grow further into seedlings. The seeds of Korean pine have deep dormancy characteristics. Natural regeneration of Korean pine is very poor under mother trees. Hoarding behavior of dispersing animals not only helps animals for food shortage period but also contributes to the dispersion of seeds of Korean pine. Among those hoarding animals, squirrel and Eurasian nutcrackers are found to be the most important dispersing agents for the seeds of Korean pine. After cone harvesting, the number of those dispersers reduced a lot since the seeds of Korean pine are very important food for them. Seed quantity of Korean pine on surface layer became very few and most of them only showed single distribution. Most of the seeds were buried under litter layer and showed a single or 2-4 seeds/cluster distribution. The case of more than 4 seeds in one cluster was few. The seed quantity of Korean pine forest on steep slopes of the research area was only 0.3% of the seed quantity in 1980 for the same forest type. If seed source of Korean pine are not protected, Korean pine forest in Mt. Changbai Nature Reserve would not maintain present feature in the future.

• The Korean Journal of Ecology
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• v.14 no.1
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• pp.1-7
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• 1991

This study was carried out to estimate the seed crop of Carpinus forest in Piagol of Mt. Chiri for six years and the results obtained were as follows; Upper two layers of Capinus forest were dominated by C. tschonoskii and Subfall tree layer ranging from 15.40 to 17.20 m in height. The distribution of seed weight of C. tsconoski was skewed to light weight classes. Most seeds fall in November. The best crop was shown in 1984, while virtually no crops in 1985. Since 1985, annual seed crop increased gradually.

• Food Science and Preservation
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• v.10 no.4
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• pp.527-533
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• 2003

This study was performed for increasing the consumption and developing the function of pumpkin(Cucurbita moschata DUCH.) seed. The changes of the contents of general chemical compositions, fatty acids, amino acids, ascorbic acid and ${\beta}$-carotene during sprouting were analyzed. Also, the bitter taste, which was produced during sprouting, were purified by using thin layer chromatography and preparative high pressure liquid chromatography. The purified bitter compound was identified by mass spectrum and nuclear magnetic resonance($^1$H '||'&'||' $\^$13/C-NMR). Weight of pumpkin seed sprout was increased to 348.4% and the length of stem was dramatically increased at 8 days. In each head and stem parts of the pumpkin seed sprout, the contents of protein and lipid were decreased, however, the contents of fiber, ash and soluble inorganic nitrogen were increased. The fatty acids of the pumpkin seed sprout were mainly represented as linoleic acid, oleic acid, palmitic acid and stearic acid. During sprouting, palmitic acid was gradually increased, reversely, linoleic acid was gradually decreased. The general amino acids of head part in the pumpkin seed sprout grown at 23$^{\circ}C$ during 8 days were orderly more contained glycine, alanine, arginine, cystein and proline. Those of free amino acids were orderly more contained arginine, threonine, alanine and glutamine. The contents of L-ascorbic acid and ${\beta}$-camtene of the pumpkin seed sprout were gradually increased with increasing sprouting days. The bitter taste material of head part of the pumpkin seed sprout was detected at Rf value 0.72 on silicagel TLC plate and separuted as one peak by HPLC. The chemical structure of the puified bitter compound was identified as a cucurbitacin glycoside by MS and NMR. The content of bitter compound at 8 days was contained 42.2 mg per 1kg sprout head.

• Journal of the Korean Society of Food Science and Nutrition
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• v.20 no.3
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• pp.225-232
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• 1991

A Study was carried out to elucidate the triglyceride compositions of the red pepper seed oils harvested from two different areas. The oil was extracted from the red pepper seed with nhexane. Each triglyceride of the oil was separated by thin layer chromatography (TLC) and fractonated by reverse phase high performance liquid chromatography (HPLC) on the basis of acyl carbon numbers, and partition number group(PN) and fatty acid composition of triglyceride were analyzed by gas liquid chromatography (GLC). From the results, it was found that the red pepper seed oils of the Chungsong and Youngyang areas consisted of 14 and 18 kinds of triglycerides, respectively. The red pepper seed oil of the Chungsong area consisted of (C18:2, C18:2, C18:2=41.0%), (C16:0, C18:2, C18:2=37.1%), and that of the Youngyang area consisted of (C18:2, C18:2, C18:2=41.0%), (C16:0, C18:2, C18:2=36.3%) and (C16:0, C16:2, C18:2=8.4%), as the major triglycerides.

• Proceedings of the Korean Vacuum Society Conference
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• 2011.02a
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• pp.189-190
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• 2011

Cu가 기존 배선물질인 Al을 대체함에 따라 resistance-capacitance (RC) delay나 electromigration (EM) 등의 문제들이 어느 정도 해결되었다. 그러나 지속적인 배선 폭의 감소로 배선의 저항 증가, EM 현상 강화 그리고 stability 악화 등의 문제가 지속적으로 야기되고 있다. 이를 해결하기 위한 방법으로 Cu alloy seed layer를 이용한 barrier 자가형성 공정에 대한 연구를 진행하였다. 이 공정은 Cu 합금을 seed layer로 사용하여 도금을 한 후 열처리를 통해 SiO2와의 계면에서 barrier를 자가 형성시키는 공정이다. 이 공정은 매우 균일하고 얇은 barrier를 형성할 수 있고 별도의 barrier와 glue layer를 형성하지 않아 seed layer를 위한 공간을 추가로 확보할 수 있는 장점을 가지고 있다. 또한, via bottom에 barrier가 형성되지 않아 배선 전체 저항을 급격히 낮출 수 있다. 합금 물질로는 초기 Al이나 Mg에 대한 연구가 진행되었으나, 낮은 oxide formation energy로 인해 SiO2에 과도한 손상을 주는 문제점이 제기되었다. 최근 Mn을 합금 물질로 사용한 안정적인 barrier 형성 공정이 보고 되고 있다. 하지만, barrier 형성을 하기 위해 300도 이상의 열처리 온도가 필요하고 열처리 시간 또한 긴 단점이 있다. 본 실험에서는 co-sputtering system을 사용하여 Cu-V 합금을 형성하였고, barrier를 자가 형성을 위해 300도에서 500도까지 열처리 온도를 변화시키며 1시간 동안 열처리를 실시하였다. Cu-V 공정 조건 확립을 위해 AFM, XRD, 4-point probe system을 이용하여 표면 거칠기, 결정성과 비저항을 평가하였다. Cu-V 박막 내 V의 함량은 V target의 plasma power density를 변화시켜 조절 하였으며 XPS를 통해 분석하였다. 열처리 후 시편의 단면을 TEM으로 분석하여 Cu-V 박막과 SiO2 사이에 interlayer가 형성된 것을 확인 하였으며 EDS를 이용한 element mapping을 통해 Cu-V 내 V의 거동과 interlayer의 성분을 확인하였다. PVD Cu-V 박막은 기판 온도에 큰 영향을 받았고, 200 도 이상에서는 Cu의 높은 표면에너지에 의한 agglomeration 현상으로 거친 표면을 가지는 박막이 형성되었다. 7.61 at.%의 V함량을 가지는 Cu-V 박막을 300도에서 1시간 열처리 한 결과 4.5 nm의 V based oxide interlayer가 형성된 것을 확인하였다. 열처리에 의해 Cu-V 박막 내 V은 SiO2와의 계면과 박막 표면으로 확산하며 oxide를 형성했으며 Cu-V 박막 내 V 함량은 줄어들었다. 300, 400, 500도에서 열처리 한 결과 동일 조성과 열처리 온도에서 Cu-Mn에 의해 형성된 interlayer의 두께 보다 두껍게 성장 했다. 이는 V의 oxide formation nergyrk Mn 보다 작으므로 SiO2와의 계면에서 산화막 형성이 쉽기 때문으로 판단된다. 또한, V+5 이온 반경이 Mn+2 이온 반경보다 작아 oxide 내부에서 확산이 용이하며 oxide 박막 내에 여기되는 전기장이 더 큰 산화수를 가지는 V의 경우 더 크기 때문으로 판단된다.

• Proceedings of the Korean Vacuum Society Conference
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• 2012.02a
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• pp.256-256
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• 2012

Cu가 기존 배선물질인 Al을 대체함에 따라 resistance-capacitance delay와 electromigration (EM) 등의 문제들이 어느 정도 해결되었다. 그러나 지속적인 배선 폭의 감소로 배선의 저항 증가, EM 현상 강화 그리고 stability 악화 등의 문제가 지속적으로 야기되고 있다. 이를 해결하기 위한 방법으로 Cu alloy seed layer를 이용한 barrier 자가형성 공정에 대한 연구를 진행하였다. 이 공정은 Cu 합금을 seed layer로 사용하여 도금을 한 후 열처리를 통해 $SiO_2$와의 계면에서 barrier를 자가 형성시키는 공정이다. 이 공정은 매우 균일하고 얇은 barrier를 형성할 수 있고 별도의 barrier와 glue layer를 형성하지 않아 seed layer를 위한 공간을 추가로 확보할 수 있는 장점을 가지고 있다. 또한, via bottom에 barrier가 형성되지 않아 배선 전체 저항을 급격히 낮출 수 있다. 합금 물질로는 초기 Al이나 Mg에 대한 연구가 진행되었으나, 낮은 oxide formation energy로 인해 SiO2에 과도한 손상을 주는 문제점이 제기되었다. 최근 Mn을 합금 물질로 사용한 안정적인 barrier 형성 공정이 보고 되고 있다. 하지만, barrier 형성을 하기 위해 300도 이상의 열처리 온도가 필요하고 열처리 시간 또한 긴 단점이 있다. 본 실험에서는 co-sputtering system을 사용하여 Cu-V 합금을 형성하였고, barrier를 자가 형성을 위해 300도에서 500도까지 열처리 온도를 변화시키며 1시간 동안 열처리를 실시하였다. Cu-V 공정 조건 확립을 위해 AFM, XRD, 4-point probe system을 이용하여 표면 거칠기, 결정성과 비저항을 평가하였다. Cu-V 박막 내 V의 함량은 V target의 plasma power density를 변화시켜 조절 하였으며 XPS를 통해 분석하였다. 열처리 후 시편의 단면을 TEM으로 분석하여 Cu-V 박막과 $SiO_2$ 사이에 interlayer가 형성된 것을 확인 하였으며 EDS를 이용한 element mapping을 통해 Cu-V 내 V의 거동과 interlayer의 성분을 확인하였다. PVD Cu-V 박막은 기판 온도에 큰 영향을 받았고, 200도 이상에서는 Cu의 높은 표면에너지에 의한 agglomeration 현상으로 거친 표면을 가지는 박막이 형성되었다. 7.61 at.%의 V함량을 가지는 Cu-V 박막을 300도에서 1시간 열처리 한 결과 4.5 nm의 V based oxide interlayer가 형성된 것을 확인하였다. 열처리에 의해 Cu-V 박막 내 V은 $SiO_2$와의 계면과 박막 표면으로 확산하며 oxide를 형성했으며 Cu-V 박막 내 V 함량은 줄어들었다. 300, 400, 500도에서 열처리 한 결과 동일 조성과 열처리 온도에서 Cu-Mn에 의해 형성된 interlayer의 두께 보다 두껍게 성장했다. 이는 V의 oxide formation energy가 Mn 보다 작으므로 SiO2와의 계면에서 산화막 형성이 쉽기 때문으로 판단된다. 또한, $V^{+5}$이온 반경이 $Mn^{+2}$이온 반경보다 작아 oxide 내부에서 확산이 용이하며 oxide 박막 내에 여기되는 전기장이 더 큰 산화수를 가지는 V의 경우 더 크기 때문으로 판단된다.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.25 no.12
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• pp.979-983
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• 2012

We proposed the ZnO thin film for a SAW filter by PLD and RF sputtering method. ZnO thin films was pre-deposited on a sapphire substrate as a seed layer by PLD method and then deposited on seed layer by RF sputtering. The surface characteristics of ZnO thin film were investigated by XRD, SEM and AFM. The minimum surface roughness was 1.92 nm and FWHM of rocking curve was $0.92^{\circ}$. We demonstrated the SAW filter with bandwidth of approximately 0.97 MHz and the center frequency of 18.72 MHz using the proposed ZnO thin film.

• Proceedings of the KIEE Conference
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• 1991.11a
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• pp.316-320
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• 1991

The dielectric properties of the ZnO varistor fabricated by the method of 3-composition seed grain was studied. In this paper, we present the C-V charateristic for the specimen. The dielectric constant and disppation which changed with additives may be explained on the basis of the deplation layer; the presence of deplation layer has been inferred by donor and state density obtained from the $1/C^2$ vs. V.

• Journal of Nutrition and Health
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• v.15 no.1
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• pp.30-38
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• 1982

Experiments were carried out in order to compare the natural antioxidants in the acetonitril extracts of raw and baked seeds of Korean sesame and perilla by thin layer and gas chromatography. The sample was dissolved in n-pentane and extracted with acetonitril and the acetonitril extract was separated by thin layer chromatography using silica gel. The spots were detected by spraying with 2, 6 -dichloroquinone -4-chlorimide, phosphomolybdic acid and dimethylamine as chromogenic reagents. Natural antioxidant, such as ${\delta}-tocopherol$ detected in raw and baked sesame and perilla seed oil by TLC and sesamol was detected only in raw and baked sesame seed oil by GC.