• Proceedings of the Korea Association of Crystal Growth Conference
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• 1999.06a
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• pp.321-335
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• 1999

Erbium(Er) doped LiNbO3(Er:LiNbO3) single crystal gibers were grown free of cracks along the c-axis by micro-pulling down method. the Er3+ concentration was distributed homogeneously along the growth axis. The samples for optical characterization were cut from as-grown single crystal fibers and polished. When the 980 nm light was incident on the sample, upconversion phenomena were observed at the green range of wavelength 510~570 nm. In addition, the intensity of upconversion was remarkably increased by increasing the concentration of Er2O3 dopant in as-grown Er:LiNbO3 crystals.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.13 no.4
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• pp.168-171
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• 2003

$YMnO_{3}$ single crystals have been grown by a floating zone technique and the optimal growth conditions were investigated. Their crystallinity and microstructure were characterized by the chemical etch pit patterns, their distribution and the compositional difference depending on the G value. In particular, the microstructural feature was interpreted in terms of compositional deviation along radial direction on (1010) growth plane.

• Corrosion Science and Technology
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• v.22 no.1
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• pp.36-43
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• 2023

Single-crystal Ni-rich NCM is a material that has drawn attention in the field of lithium-ion batteries due to its high energy density and long cycle life. In this study, we investigated the properties of single-crystal NCM 811 and its potential for use in lithium-ion batteries. High-quality single crystals of NCM 811 were successfully synthesized by crystal growth via a flux method. The single-crystal nature of the samples was confirmed through detailed characterization techniques, such as scanning electron microscopy and x-ray diffraction with Rietveld refinement. The crystal structure and electrochemical performances of the single-crystal NCM 811 were analyzed and compared to its poly-crystal counterpart. The results indicated that single-crystal NCM 811 had electrochemical performance and thermal stability superior to poly-crystalline NCM 811, making it a suitable candidate for high-performance batteries. The findings of this study contribute to a better understanding of the characteristics and potential of single-crystal NCM 811 for lithium-ion batteries.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.13 no.3
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• pp.132-138
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• 2003

A stoichiometric mixture for $CdIn_2Te_4$ single crystal was prepared from horizontal electric furnace. The $CdIn_2Te_4$ single crystal was grown in the three-stage vertical electric furnace by using Bridgman method. The $CdIn_2Te_4$ single crystal was evaluated to be tetragonal by the power method. The (001) growth plane of oriented $CdIn_2Te_4$ single crystal was confirmed from back-reflection Laue patterns. The carrier density and mobility of $CdIn_2Te_4$ single crystal measured with Hall effect by van der Pauw method are $8.61\times 1016 \textrm {cm}^{-3}$ and 242 $\textrm{cm}^2$/V.s at 293 K, respectively. The temperature dependence of the energy band gap of the $CdIn_2Te_4$ single crystal obtained from the absorption spectra was well described by the Varshni's relation, $1.4750ev - (7.69\times10^{-3})\; ev/k)\;T^2$/(T + 2147k).The crystal field and the spin-orbit splitting energies for the valence band of the $CdIn_2Te_4$ single crystal have been estimated to be 0.2704 eV and 0.1465 eV, respectively, by means of the photocurrent spectra and the Hopfield quasicubic model. These results indicate that the splitting of the $\Delta$so definitely exists in the $\Gamma_7$ states of the valence band of the $CdIn_2Te_4$ single crystal. The three photocurrent peaks observed at 10 K are ascribed to the $A_{1-} B_{1-}$ and Cl-exciton peaks for n = 1.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.9 no.6
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• pp.547-552
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• 1999

Langasite$(La_{3}Ga_{5}SiO_{14})$ single crystal was successfully grown by Floating Zone (FZ) method and characterized. The growth rate was 1.5 mm/h and the rotation speed was 15 rpm for an upper rotation and 13 rpm for a lower rotation. The grown crystal was 12 mm in length and 6 mm in diameter. The grown crystal was dark orange color and it was grown along [001] direction. The composition of grown crystal and the structure were analyzed using XRD and WDS. The electrical properties of grown crystal at various frequencies and temperatures were discussed.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.1 no.1
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• pp.117-126
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• 1991

Silicon single crystal is the most frequently used materials for the semiconductor device fabrication, The crystal growth techniques have been steadily improving for achieving a greater degree of crystal perfection and large ingot size. This report present the advantages, disadvantages and technical problems of the various crystal pulling technique briefly on the economic impact of productivity. Also, future directions of the pulling technique and process including the economical and quantitative aspects are deal with.

• Proceedings of the Korea Association of Crystal Growth Conference
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• 1996.06a
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• pp.537-537
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• 1996

• Journal of Magnetics
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• v.19 no.4
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• pp.333-339
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• 2014

Single crystal growth of $BaFe_{12}O_{19}$ by the solid state crystal growth method was attempted. Seed crystals of ${\alpha}-Fe_2O_3$ were pressed into pellets of $BaFe_{12}O_{19}$ + 2 wt% $BaCO_3$ and heat-treated at temperatures between $1150^{\circ}C$ and $1250^{\circ}C$ for up to 100 hours. Instead of single crystal growth taking place on the seed crystal, BaO diffused into the seed crystal and reacted with it to form a polycrystalline reaction layer of $BaFe_{12}O_{19}$. The microstructure, chemical composition and structure of the reaction layer were studied using scanning electron microscopy-energy dispersive spectroscopy (SEM-EDS), x-ray Diffraction (XRD) and micro-Raman scattering and confirmed to be that of $BaFe_{12}O_{19}$. XRD showed that the reaction layer shows a strong degree of orientation in the (h00)/(hk0) planes in the sample sintered at $1200^{\circ}C$. $BaFe_{12}O_{19}$ layers with a degree of orientation in the (hk0) planes could also be grown by heat-treating an ${\alpha}-Fe_2O_3$ seed crystal buried in $BaCO_3$ powder.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.13 no.4
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• pp.153-156
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• 2003

Pure and Ethylenediaminetetraacetic acid (EDTA) doped L-arginine phosphate (LAP) single crystals were grown from the aqueous solution by temperature lowering method. The effect of EDTA additive on the solubility and metastable zone width of LAP solution has been investigated. Addition of EDTA has enhanced the metastable zone width of LAP and hence bulk crystals could be grown. The growth rate along the [100] direction increases with EDTA additive. Powder X-ray diffraction and FTIR studies reveal the absence of EDTA in the lattice of LAP, This reveals that the addition of EDTA to LAP doesn't influence the crystallinity. However, the transmittance and NLO properties significantly increase with EDTA additive and hence bulk LAP crystals are useful for laser fusion experiments.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.13 no.4
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• pp.172-175
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• 2003

We have investigated effects of the lattice mismatch between the LPE films and the substrates. We have grown $La_{2-x}Sr_{x}CuO_{4}$(x=0.1 to 0.15) single crystalline films on single crystalline substrates having different lattice parameter ratio c/a e.g., $La_{2-x}Sr_{x}Cu_{1-y}Zn_{y}O_{4},\;La_{2-x}Ba_{x}CuO_{4},\; LaSrAlO_{4}\;and\;La_{2-x}Sr_{x}Cu_{1-y}Al_{y}O_{4}$ etc., using the IR-LPE technique. The superconducting properties of the grown films were found to vary significantly depending on the lattice mismatch with different substrates.