• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2007.11a
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• pp.81-82
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• 2007

The stochiometric mix of evaporating materials for the $CdGa_2Se_4$ single crystal thin films was prepared from horizontal furnace. To obtain the single crystal thin films, $CdGa_2Se_4$ mixed crystal was deposited on thoroughly etched semi-insulating GaAs(100) substrate by the Hot Wall Epitaxy (HWE) system. The source and substrate temperature were $630^{\circ}C\;and\;420^{\circ}C$, respectively. After the as-grown single crystal $CdGa_2Se_4$ thin films were annealed in Cd-, Se-, and Ga -atmospheres, the origin of point defects of single crystal $CdGa_2Se_4$ thin films has been investigated by PL at 10 K. The native defects of $V_{Cd},\;V_{Se},\;Cd_{int},\;and\;Se_{int}$ obtained by PL measurements were classified as donors or acceptors. And we concluded that the heat-treatment in the Cd-atmosphere converted single crystal $CdGa_2Se_4$ thin films to an optical p-type. Also, we confirmed that Ga in $CdGa_2Se_4$/GaAs did not form the native defects because Ga in single crystal $CdGa_2Se_4$ thin films existed in the form of stable bonds.

• Proceedings of the Korea Association of Crystal Growth Conference
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• 1999.12a
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• pp.93-99
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• 1999

It is definite trend that the functional devices are to be integrated by miniaturizing of individual components. Bulk crystals turn into wafer form, while thin film of the functional materials is being fabricated for single and multi-layer devices. In addition, single crystals with multi-function performance would be desirable for further miniaturization. crystal growers have the responsibility for synthesis single crystals work to meet ever increasing requirement of future devices.

• Proceedings of the Korea Association of Crystal Growth Conference
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• 1997.06a
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• pp.139-143
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• 1997

The doping effects of Mg and/or Fe ions on congruent LiNbO$_3$ single crystal growth were studied in order to clarify the roles of MgO in Fe doped LiNbO$_3$ single crystals. The effective distribution coefficienct of Fe was found decreased drastically from 0.85 to 0.5 by the addition of MgO into the LiNbO$_3$ melt. M ssbauer spectra revealed that the addition of MgO reduces the occurrence of Fe2+ ions during growth in air. Therefore, it is likely that there would be two important roles of MgO in Fe doped LiNbO$_3$. One is to suppress the incorporation of all Fe ions, and the other is to reduce the concentration of Fe2+ ions among the total Fe ions.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.4 no.3
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• pp.223-229
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• 1994

$KTP(KTiOPO_4)$ single crystals have been hydrothermally grown in KOH solutions. Properties and Raman spectra of grown crystal were investigated. The most effective solvents for the crystal growth of KTP were KOH and KF solutions. In this study, the properties of KTP single crystals grown hydrothermally at $500^{\circ}C$ in 9 m KOH solution were measured. The following results were obtained : lattice parameters ; a=1.281 nm and c=1.058 nm, density ; $2.94 g/cm^3$, Vickers hardness ; $562kg/cm^2$, refractive indices ; $n_e=1.740$ and $n_e= 1.747.$ And Raman spectra of hydrothermal growth KTP single crystal have been investigated at room temperature under atmospheric pressure. As a result, the $A_1$ modes agree very well with KTP single crystal of high temperatures solution growth but the behavior of $B_2$ modes were slightly different.

• Proceedings of the Korea Association of Crystal Growth Conference
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• 1999.06a
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• pp.305-320
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• 1999

It was grown Er2O3 doped LiNbO3 single crystal thin films with high crystal quality by liquid phase epitaxial (LPE) method. Er2O3 was doped with a concentration of 1, 3, and 5 mol% respectively. After the growth of single crystal thin film, we examined the crystallinity and the lattice mismatch along the c-axis between the film and the substrate with the variation of Er2O3 dopant using X-ray double crystal technique. There were no lattice mismatches along the c-axis for the undoped and the films doped with 1 and 3 mol% of Er2O3. For 5 mol% of Er2O3 doped film, there was a lattice mismatch of 7.86x10-4nm along the c-axis.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.9 no.3
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• pp.295-298
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• 1999

High quality of $Er_{2}O_{3}$ doped $LiNbO_{3}$ single crystal thin films were grown by the liquid phase epitaxial (LPE) method using $Er_{2}O_{3}$ doped at concentrations of 1,3, and 5 mol% respectively. After the growth of single crystal thin film, the crystallinity and the lattice mismatch along the c-axis between the film and the substrate was examined as a function of the variations of{{{{{Er}_{2}{O}_{3}}}}} dopant concentration using a X-ray double crystal technique. There was no lattice mismatch along the c-axis for the undoped film and those doped with 1 and 3 mol% of $Er_{2}O_{3}$. For 5 mol% of $Er_{2}O_{3}$ doped film, the lattice mismatch was $7.86{\times}10^{-4}$nm along the c-axis.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.8 no.4
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• pp.539-543
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• 1998

The relationship of growth-in defects such as crystal originated particles (COP), flow pattern defects(FPD), laser scattering tomography defects (LSTD) was investigated in Cz-Si single crystals which had different pulling speed during crystal growing. It is concluded that the density and radial distribution of grown-in defects is strongly dependent on the pulling speed. And as the generation areas of these grown-in defects in a wafer are identical in radial position, they can be generated from same origin during crystal growing.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.3 no.2
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• pp.162-166
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• 1993

Spodumene$(LiAlLi_2O_6)$ single crystal was grown by Floating Zone process using the image furnace having the halogen lamp as heat sources. The crystal had the dimension of 50~60mm length and 6~8mm diameter. The colors of as-grown crystals were green, black and pale green respectively. The composition of the crystal was analized by XRD and FUR measurement. Growth orientation was examined by Laue back reflection pattern and for measuring the light transmittance, OPtical transmittance was measured.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.6 no.3
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• pp.301-308
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• 1996

Domain structure and properties of LiNbO3 single crystals grown by continuous method (Orr's method) were characterized. It was found that the growth striation of the grown crystals correspond with domain structure and the positive-negative domains were repeated with the perpendicular direction to the C axes. The formation of negative domains were related to the rapid crystal growth rate. The measured dielectric constant of the grown crystal was 140∼150 at 100 kHz at the room temperature and Curie point was 1153℃.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.21 no.5
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• pp.193-198
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• 2011

Recently sapphire crystals are used in LED applications. The Czochralski (CZ) growth process is one of the most important techniques for growing high quality sapphire single crystal. A successful growth of perfect single crystals requires the control of heat and mass transport phenomena in the CZ growth furnace. In this study, the growth processes of the sapphire crystal in an inductively heated CZ furnace have been analyzed numerically using finite element method. The results shown that the high temperature positions moved from the crucible surface to inside the melt and the crystal-melt interface changed to the flat shape when the rpm was increased. Also the crystal-melt interface shape has been influenced by the shoulder shape of the grown crystal during the initial stage.