• Journal of the Korean Crystal Growth and Crystal Technology
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• v.29 no.4
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• pp.173-178
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• 2019

In this study, we demonstrated a characterization of ${\alpha}-Ga_2O_3$ grown on a cone-shape patterned sapphire substrate by using the halide vapor phase epitaxy. An ${\alpha}-Ga_2O_3$ was grown on different size of PSS and c-plane sapphire substrate for comparison to confirm the effect of PSS. In addition, growth time of ${\alpha}-Ga_2O_3$ was gradually increased to confirm growth mechanism of ${\alpha}-Ga_2O_3$ grown on the PSS. A growth temperature was changed to $470-550^{\circ}C$. It can be analyzed growth conditions and mechanisms on the cone-shape PSS, resulting in a significant decrease in the FWHM value of an asymmetric plane (10-14) of ${\alpha}-Ga_2O_3$, due to lateral growth that occurs during the growth process.

• Bulletin of the Korean Chemical Society
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• v.32 no.12
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• pp.4371-4376
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• 2011

In this work, we investigate the growth behavior of silicon oxide nanowires via a solid-liquid-solid process. Silicon oxide nanowires were synthesized at $1000^{\circ}C$ in an Ar and $H_2$ mixed gas. A pre-oxidized silicon wafer and a nickel film are used as the substrate and catalyst, respectively. We propose two distinctive growth modes for the silicon oxide nanowires that both act as a unique solid-liquid-solid growth process. We named the two growth mechanisms "grounded-growth" and "branched-growth" modes to characterize their unique solid-liquid-solid growth behavior. The two growth modes were classified by the generation site of the nanowires. The grounded-growth mode in which the grown nanowires are generated from the substrate and the branchedgrowth mode where the nanowires are grown from the side of the previously grown nanowires or at the metal catalyst drop attached at the tip of the nanowire stem.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.7 no.1
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• pp.59-69
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• 1997

The growth and microstructural characterization of epitaxial yttrium silicide ($YSi_2$) on the (100)Si substrate are investigated. The $YSi_2$ film grow epitaxilly through the solid phase reaction during vacuum annealing above $400^{\circ}C$. The epitaxial relationships between the hexagonal $YSi_2$ film and the (100)Si substrate are [0001]$YSi_2$//[011]Si and [0001]$YSi_2$//[011]Si in the (1100)$YSi_2$//(100)Si plane relation. The YSi$_2$ film consists of the two types of domains which have two different azimuthal orientations making an angle of $90^{\circ}$ to each other. The two types of domains in the $YSi_2$film are equivalent in volume fraction and crystalline quality, which has been proved from the equivalent integrated intensities of (2201) asymmetric reflection of X-ray diffraction. The formation of a double -domain structure is discussed on the basis of geometrical matching at interface between the (1100)$YSi_2$ film and the (100)Si substrate, and growth model is proposed.

• Journal of the Korean Society of Industry Convergence
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• v.20 no.5
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• pp.351-357
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• 2017

Growing plant in potting media without soil is known as Soilless cultivation. This method is used mostly in greenhouse cultivation to increase horticultural commodities production. Peat moss is commonly utilized as potting media substrate because of its characteristic. However, peat moss price is high because of the quantity of peat moss in nature has been decreased. Recently, most of the research is conducted to find the alternative growing medium to cultivate horticulture plant in potting media. Perlite and rice husk ash were mentioned that had a potent as alternative growing media for seasonal plants to increase agriculture production due to the lack of production area. This study aimed to determine the effect of using different substrate and growth performance of chili. The method used was the soilless cultivation. The chili was planted in the pot with perlite media, rice husk ash media, and peat moss media. The chili was measured after 65 days after planting. The result showed that rice husk ash and perlite were more potentials in chili growth performance than peat moss. Rice husk ash had the significant result of plant height. While, Perlite effect on root length, plant weight, leaf length, and stem diameter. The best alternative for cultivation chili without substrate based on this research was perlite then rice husk ash and peat moss.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.16 no.6
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• pp.93-107
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• 2013

Construction of an artificial wetland for the growth of Sphagnum palustre with emergent macrophytes (Phragmites australis, Typha angustifolia, and Zizania latifolia) was firstly tried and the growth of those plant components according to various environmental combinations has been monitored for three years. Above-ground dry weight of Z. latifolia ($1,500g/m^2$) was higher than T. angustifolia ($900g/m^2$) and P. australis ($500g/m^2$) under most environmental conditions. In overall, planted emergent macrophytes seemed to prefer polishing sand without moss peat as a substrate and relatively deep water-depth condition (20cm) rather than shallow water-depth (5cm). Despite of high calcium content in inflow water (> 15ppm) into the constructed wetland, S. palustre populations have survived in most experimental plots during the monitoring period. Substrate layer including moss peat with high surface-area might play a role as an ion-filter. After three years, relatively thicker litter-layer in Z. latifolia plots due to vigorous growth appeared to heavily depress S. palustre by physical compressing and complete shading processes. Most of all, for the continuous growth of S. palustre, physio-chemical characteristics of water and substrate must be carefully managed. In addition, companion emergent species should be also cautiously selected not to depress S. palustre by much litter production. We suggest P. australis and T. angustifolia as companion species rather than Z. latifolia.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.18 no.1
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• pp.10-14
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• 2008

We synthesized GaN nanowires with high quality using the vapor phase epitaxy technique. The GaN nanowires were obtained at a temperature of $950^{\circ}C$. The Ar and $NH_3$ flow rates were 1000 sccm and 50 sccm, respectively. The shape of the GaN nanowires was confirmed through FESEM analysis. We were able to conclude that the GaN nanowires synthesized via vapor-solid (VLS) mechanism when the source was closed to the substrate. On the other side, the VS mechanism changed to vapor-liquid-solid (VLS) as the source and the substrate became more distant. Therefore, we can suggest that the large amount of Ga source from initial growth interrupt the role of catalyst on the substrate.

• Horticultural Science & Technology
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• v.19 no.1
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• pp.92-97
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• 2001

This experiment was conducted to find out optimum substrate and concentration of nutrient solution for mass production of sweet basil by pot culture. Growth depending on concentration of nutrient solution was different to some extent; the growth of plants was usually better in one-fold and two-fold concentration of nutrient solution but three-fold one was poor. Plants grown in cocopeat showed better growth, but peatmoss gave an adverse effect. Sweet basil grown in substrate mixed with cocopeat and perlite (1:1, v:v) was highest in essential oil content. After all, cultural practice by one-fold concentration of herb nutrient solution in substrate mixed with cocopeat and perlite (1:1, v:v) was recommended for better growth and higher essential oil content of sweet basil.

• Applied Science and Convergence Technology
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• v.24 no.4
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• pp.117-124
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• 2015

A direct growth method of graphene on insulating substrate without catalyst etching and transfer process was developed using Au/Ni/a-C catalyst system. During the growth process, behavior of the Au/Ni catalyst was investigated using EDX, XPS, SEM, and Raman spectroscopy. The Au/Ni catalyst layer was evaporated during growth process of graphene. The graphene film was composed mono-layer flakes. The transmittance of the graphene film was ~80.6%.

• Journal of the Korean Institute of Telematics and Electronics
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• v.21 no.4
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• pp.17-23
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• 1984

A model analysis of pattern shift in the epitaxial growth of silicon on (111) substrates was performed. The growth rate anisotropy was considered as the most important affecting factor of pattern shift, and for the model establishment the off angle of the substrate and the process temperature were taken as the variables. We derived a theoretical equation of pattern shift by assuming the growth rate anisotropy as the trigonometric sine function of the off angle of the substrate and defining the growth rate anisotropy factor related to the process temperature. The pattern shift ratio calculated by this model had the same tendency with the experimental ones, which, however, were about twice greater than those. It was supposed that this discrepailcy was due to the second order affecting factor such as facetting and step broadening which had been exluded in model establishment.

• 한국정보디스플레이학회:학술대회논문집
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• 2002.08a
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• pp.694-696
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• 2002

Growth behaviors of carbon nanotubes (CNTs) are studied in terms of catalyst by using scanning electron microscopy and transmission electron microscope (TEM). Catalyst films deposited on various substrates are agglomerated into nano-islands during the heat-up to the growth temperature. In particular, we focus on the direct investigation of the microstructures of the CNTs and the interface of CNTs-catalyst-substrate using cross-sectional TEM. We investigate relationship to the subsequent CNTs growth on each nucleation site. The growth of CNTs depends on the catalyst itself but not the silicide formation between the catalyst and the substrate.