• Proceedings of the Materials Research Society of Korea Conference
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• 2006.05a
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• pp.24.1-24.1
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• 2006

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.1 no.1
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• pp.66-73
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• 1991

During the growth of macroscopically dislocation-free Czochralski silicon crystal, micro precipitates causing stacking faults in the silicon wafer during the oxidation are formed Thermal history the cryscausing acquire during the growth process is known to be a key factor determining the nucleation of this micro precipitates. In this article, various mechanisms suggested on the formation of microdefects in the silicon crystal are reviewed to secure the nucleation mechanism of the micro precipitates causing OSF whose pattern is normally ring or annular in CZ silicon crytal. B-defects which are known as vacancy clustering are considered to be the heterogeneous nucleation sites for the micro precipitates causing OSF in the CZ silicon crystals.

• Korean Journal of Crystallography
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• v.7 no.1
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• pp.30-35
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• 1996

Calcite(CaCO3) single crystals were grown hydrothermally and transmittance of as grown crystals was measured. Instead of platinium, teflon was lined onto the wall of autoclave to prevent the corrosion of autoclave wall by acidic NH4Cl solution. Spontaneous nucleation and growth of calcite crystal on teflon was reduced considerably by addition of NaCl and /or CH3COOH and applying low temperature gradient. When the temperature gradient exceeded to a few degrees from the critical temperature gradient(6-7℃), spontaneous nucleation and growth was rapidly increased in any hydrothermal solutions. Precise temperature control is thought to be the most important factor for the growth of calcite single crystal by hydrothermal technique. As grown calcite single crytal showed high transmittance compared to natural one by UV-visible analysis.

• Korean Journal of Crystallography
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• v.1 no.1
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• pp.19-28
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• 1990

6H-SiC is a promising material (Eg=3.0eV) for blue light-emitting doide and high-temperature semiconducting device. In the experiment, single crystals of a-SiC have been grown by the sublimation method to fabricate blue light~emitting diode. During the growth of a-SiC single crystals, a temperature Vadient, yonh temperature and pressure ranges were kept 44℃/cm , 1800-1990℃ and 50-1000 mTorr, respectively. Single crystals obtained in Acheson furnace were used as seed crystals. Polarizing microscopy and back-reflection X-ray Laue diffraction showed that the a-SiC crystal was epitaxially and on the seed crytal. It was found by XRD analysis that when other growth conditions were the same, a-SiC was grown at the temperature above 1840℃ and 3C-SiC was gown at lower temperature or under low supersaturation of vapor. The carrier type. concentration and mobility were measured be hole(p-type), 7.6x1014cm-3 and 19cm2V-1sec-1, respectively, by van der Pauw method.