• Journal of the Korean Crystal Growth and Crystal Technology
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• v.1 no.1
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• pp.82-91
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• 1991

Molecular beam epitaxial growth of GaAs on Si substrate and the results on its analysis are reported. Epitaxy was performed on two different types of the substrate under various grwth conditions, and was analyzed by scanning and transmission electron microscopes, X-ray diffractometer, photoluminescence and Hall measurements. GaAs epitaxial layer has better crystalline quality when it was grown on a tilt-cut substrate. The stress seems to be releaxed more easily when multi-quantum well was introduced in the buffer layer. The epilayer was doped unintentionally with Si during growth due to the diffusion of the substrate. Also observed is that the quantum efficiency of excitonic radiative recombination of the heteroepitaxy is not as good as that of the homoepitaxy in the same doping level.

• Proceedings of the Korea Association of Crystal Growth Conference
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• 1997.06a
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• pp.253-259
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• 1997

The iron doped GaAs single crystals were grown by liquid phase epitaxial method and its some physical properties were evaluated with a view to investigate the crystal quality and emission property. The isomer shift of 0.303mm/sec is calculated from low-temperature M ssbauer spectroscopy and we know that charge state of iron ion is 3+ in GaAs crystal. In low temperature photoluminescence, the deep emission bands with wide-line width have been observed at 0.99eV and 1.15eV in addition to sharp excitonic peaks. We attributed that these deep emissions are originated from substitutional Fe-acceptor which has charge state of 3+ and 2+, respectively.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.14 no.5
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• pp.215-219
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• 2004

ZnO epitaxial films have been grown on a (0001)sapphire substrate by RF magnetron sputtering. The single crystalline ZnO films were grown at the condition of growth rate of about 0.1~0.2 $\mu\textrm{m}$/hr and the substrate temperature of $600^{\circ}C$. The film thickness was about 400~500 nm. The thin film quality and micro-structure have been evaluated by XRD and TEM observation.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.10 no.5
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• pp.350-355
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• 2000

The fabrication of sapphire wafer in C plane has been developed by horizontal Bridgeman method and GaN based semiconductor epitaxial growth has been carried out in metal organic chemical vapour deposition. The single crystalline ingot of sapphire has been utilized for 2 inch sapphire wafers and wafer slicing and lapping machines were designed. These several steps of lapping processes provided the mirror-like surface of sapphire wafer. The measurements of the surface flatness and the roughness were carried out by the atomic force microscope. The GaN thin film growth on the developed wafer was confirmed the wafer quality and applicability to blue light emitting devices.

• Proceedings of the Korea Association of Crystal Growth Conference
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• 1997.06a
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• pp.237-242
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• 1997

• Transactions on Electrical and Electronic Materials
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• v.10 no.2
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• pp.40-43
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• 2009

The authors fabricated a nanopatterned surface on a GaN thin film deposited on a sapphire substrate and used that as an epitaxial wafer on which to grow an InGaN/GaN multi-quantum well structure with metal-organic chemical vapor deposition. The deposited GaN epitaxial surface has a two-dimensional photonic crystal structure with a hexagonal lattice of 230 nm. The grown structure on the nano-surface shows a Raman shift of the transverse optical phonon mode to $569.5\;cm^{-1}$, which implies a compressive stress of 0.5 GPa. However, the regrown thin film without the nano-surface shows a free standing mode of $567.6\;cm^{-1}$, implying no stress. The nanohole surface better preserves the strain energy for pseudo-morphic crystal growth than does a flat plane.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.5 no.1
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• pp.37-43
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• 1995

The proper choice of the solvent is a prerequisite for solution growth of silicon. In the present work, the temperature to dissolve at least 1 atomic% silicon was calculated in various molten solvents.

• Proceedings of the Korea Association of Crystal Growth Conference
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• 1996.06a
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• pp.509-510
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• 1996

• Proceedings of the Korean Magnestics Society Conference
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• 2009.12a
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• pp.190-190
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• 2009

We report the epitaxial growth of MgO and CoFe/MgO on Ge (001) substrates using molecular beam epitaxy. It was found that the epitaxial growth of a MgO film on Ge could be realized at a low growth temperature of $125{\pm}5^{\circ}C$ and the MgO matches the Ge with a cell ratio of $\sqrt{2}$:1 which renders MgO rotated by $45^{\circ}$ relative to Ge. In-situ and ex-situ structural characterizations reveal the epitaxial crystal growth of bcc CoFe/MgO on Ge with the in-plane crystallographic relationship of CoFe(001)[100] || MgO(001)[110] || Ge(001)[100], exhibiting sharp interfaces in the (001) matching planes. The saturation magnetization of the sample is $1430{\pm}20$ emu/cc, which is comparable to the value of bulk CoFe.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.12 no.4
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• pp.215-221
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• 2002

Epitaxial Si layers were deposited on (100) Si substrates by hot-wall chemical vapor deposition (CVD) technique using the $SiH_2Cl_2/H_2$chemistry. Thermochemical calculations of the Si-H-Cl system were carried out to predict the window of actual Si deposition process and to investigate the effects of process variables (i.e., deposition temperature, reactor pressure, and input gas molar ratio ($H_2/SiH_2Cl_2$)) on the epitaxial growth. The calculated results were in good agreement with the experiment. Optimum process conditions were found to be the deposition temperature of 850~$950^{\circ}C$, the reactor pressure of 2~5 Torr, and the input gas molar ratio ($H_2/SiH_2Cl_2$) of 30~70, providing device-quality epitaxial layers.