• Journal of Ecology and Environment
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• v.32 no.3
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• pp.183-189
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• 2009

This research focused on the effects of fragmentation on moth diversity in an agricultural land-scape by comparing moth species richness and abundance between hillocks and young secondary forests. We examined five sites from the southwestern part of South Korea: three sites from hillock forest and two from secondary forest. We collected moths bi-weekly from April to October for a 2-year period (2006-2007) with a UV light trap that usually attracts moths within 30 meters. Tree species richness and abundance in $20m{\times}20m$ plots at each moth sampling site showed a substantial difference in tree diversity between the two types of forest habitats. The total abundance and richness of moth species were higher in secondary forests (541 species with 4,998 individuals) than in hillock forests (423 species with 3,913 individuals), irrespective of the distance among the sites. An ordination analysis with NMDS showed that habitat is the most important factor of grouping sites. The food preferences of the dominant moth species i,n each habitat were closely related to the habitat type.

• Proceedings of the IEEK Conference
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• 2001.06b
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• pp.49-52
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• 2001

The electrochemical characteristics of Alalloy thin film with low impurity concentrations AIZr deposited by using do magnetron co-sputtering deposition are investigated for the applications as gate bus line in the TFT-LCD panel. AlZr thin films were deposited various atomic percent of Zr. For increasing Zr atomic percent the hillock density was decreased and the resistivity was increased. The deposited thin films show the decrease of resistivity and the increase of grain size after the RTA at 300 $^{\circ}C$for 20 min.. Moreover, the resistivity of AIZr does not show appreciable grain size dependence after RTA. It is concluded that the decrease of resistivity after RTA is due to the increase of grain size. The annealed AIZr(at.0.9%) is found to be hillock free. The electrode potentials of AIZr were less than ITO's (-1.4V) and the etching rate of AIZr(at.0.9%) was 3.8587ng/sec. in KOH(10%) solution. Caculation results reveal that the AIZr(at.0.9%) thin film can be applicable to gate line of 25" UXGA class TFT-LCD panels and can not be applicable to data line.line.

• Journal of the Korean institute of surface engineering
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• v.14 no.3
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• pp.137-141
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• 1981

니켈 도금의 표면 조직과 두께에 따른 조직의 변화를 투과 전자 현미경을 사용하여 관찰하였다. epitaxial deposit층의 두께는 도금 용액 속에 들어있는 외부 물질에 따라 변화하게 되며, substrate의 결정 방향에 따라 또한 변화한다. (110)면 보다는 (100)면에 도금했을 때 epitaxial deposit 층의 두께가 더 큰 것을 알 수 있었다. non-epitaxial 층으로 변화되는 과정은 hillock의 생성과 계속되는 Twinning에 의해 이루어졌다.

• Proceedings of the Korean Vacuum Society Conference
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• 1997.02a
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• pp.196-196
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• 1997

• Proceedings of the KAIS Fall Conference
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• 2000.10a
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• pp.185-193
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• 2000

이방성 습식 식각을 이용하여 멤브레인을 제작하기 위하여 KOH-IPA의 식각액을 사용하여 단결정 실리콘 기판을 이방성으로 식각을 하고, 각 용액에 대한 식각 특성을 관찰하였다. 식각률은 식각액의 온도와 농도에 의존하며, 패턴 형성 방향과 식각액의 농도에 따라 식각 형태가 다르게 나타났다. 패턴은 Primary Flat에 45°로 기울여 형성되었으며 20wt·% KOH 80℃ 이상에서는 U-groove, 그 이하의 온도와 농도에서는 V-groove 식각 형태를 관찰할 수 있었다. 각 면에 대한 식각률 차이에 의해서 생기는 Hillock은 온도와 농도가 높아짐에 따라 줄어들었고, 재식각을 퉁하여 현저하게 줄어듦을 알 수 있었다.

• Korean Journal of Environmental Biology
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• v.39 no.2
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• pp.156-159
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• 2021

Arcuphantes catillus n. sp., a new species of the genus Arcuphantes Chamberlin and Ivie, 1943 is described from Korea. The present species is distinguishable from its known similar congeners by a conspicuous proximal process and a blunt lateral process of the paracymbium, feathery tipped lamellar extension of the pseudolamella, and bowl-like posterior part of radix. The present new species was collected from the leaf litter layer of mixed forest on a hillock around rice fields with a pitfall trap.

• Journal of the Korean Vacuum Society
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• v.9 no.2
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• pp.162-166
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• 2000

High quality $Si_3N_4$ metal-insulator-metal (MIM) capacitors were realized by plasma enhanced chemical vapor deposition (PECVD). Titanium nitride (TiN) adapted as a diffusion barrier reduced the interfacial reaction between $Si_3N_4$ dielectric layer and aluminum metal electrode showing neither hillock nor observable precipitate along the interface. The capacitance and the current-voltage characteristics of the MIM capacitors showed that the minimum thickness of $Si_3N_4$ layer should be limited to 500 $\AA$ under the present process, below which most of the capacitors were electrically shorted resulting in the devastation of on-wafer yield. According to the transmission electron microscopy (TEM) on the cross-sectional microstructure of the capacitors, the dielectric breakdown was caused by slit-like voids formed at the interface between TiN and $Si_3N_4$ layers when the thickness of $Si_3N_4$ layer was less than 500 $\AA$. Based on the calculation of thermally-induced residual stress, the formation of voids was understood from the mechanistic point of view.

• Journal of the Microelectronics and Packaging Society
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• v.11 no.2 s.31
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• pp.53-58
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• 2004

To facilitate the observation of the electromigration of 63Sn-37Pb eutectic solder, strip-type samples were fabricated by solder evaporation. The electromigration test for the 63Sn-37Pb solder strip was conducted at temperatures of $80{\sim}150^{\circ}C$ and the current densities of $1{\times}10^4{\sim}1{\times}10^5\;A/cm^2$. With increasing temperature and the current density, mean-time-to-failure(MTTF) decreased due to the formation of hillock and void in the solder strip. The activation energy for the electromigration in the 63Sn-37Pb solder strip was analyzed as $0.16{\sim}0.5\;eV$ using Black's equation.

• Journal of Sensor Science and Technology
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• v.12 no.6
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• pp.282-288
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• 2003

We report the growth of HgCdTe by metal organic vapor phase epitaxy (MOVPE), using (211)B CdTe/Si substrates grown by molecular beam epitaxy (MBE). The surface morphology of these films is very smooth with hillock free. The etch pit densities (EPD) and full widths at half maximum (FWHM) of x-ray rocking curves exhibited that the crystalline quality of HgCdTe epilayer on MBE grown CdTe/Si was improved compare to HgCdTe on GaAs substrate. The Hall parameters of undoped HgCdTe layers on CdTe/Si showed n-type behavior with carrier concentration of $8{\times}10^{14}/cm^3$ at 77K. But HgCdTe on GaAs showed p-type conductivity due to in corporation of p-type impurities during GaAs substrate preparation. It is thought that these results are applicable for large area HgCdTe forcal plane arrays of $1024{\times}1024$ format and beyound.

• Journal of the Korean institute of surface engineering
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• v.56 no.2
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• pp.160-168
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• 2023

Recently, investigation on metallization is a key for a stretchable display. Amorphous metal such as Ni and Zr based amorphous metal compounds are introduced for a suitable material with superelastic property under certain stress condition. However, Ni and Zr based amorphous metals have too high resistivity for a display device's interconnectors. In addition, these metals are not suitable for display process chemicals. Therefore, we choose an aluminum based amprhous metal Al-Mo as a interconnector of stretchable display. In this paper, Amorphous Forming Composition Range (AFCR) for Al-Mo alloys are calculated by Midema's model, which is between 0.1 and 0.25 molybdenum, as confirmed by X-ray diffraction (XRD). The elongation tests revealed that amorphous Al-20Mo alloy thin films exhibit superior stretchability compared to pure Al thin films, with significantly less increase in resistivity at a 10% strain. This excellent resistance to hillock formation in the Al20Mo alloy is attributed to the recessed diffusion of aluminum atoms in the amorphous phase, rather than in the crystalline phase, as well as stress distribution and relaxation in the aluminum alloy. Furthermore, according to the AES depth profile analysis, the amorphous Al-Mo alloys are completely compatible with existing etching processes. The alloys exhibit fast etch rates, with a reasonable oxide layer thickness of 10 nm, and there is no diffusion of oxides in the matrix. This compatibility with existing etching processes is an important advantage for the industrial production of stretchable displays.