Growth of (0001) AlN Single Crystals Using Carbon-Face SiC as Seeds

Growth of AlN single crystals using carbon-polar surface of SiC substrate by PVT growth method has been attempted. AlN growth on the carbon-face was dominated by spiral growth mode under the applied experimental conditions and further, an abrupt interface was observed between AlN layer and the substrate. Broad XRD rocking curve of the sample, taken from bottom part of the crystal, indicates a high density of misfit dislocations near the interface and further a shift of E2(high) phonon mode in the Raman measurements shows a significant misfit stress. The XRD-RC FWHM values of symmetric 002 and asymmetric 102 reflections (top part of the crystal) are 380 and 300 arcsec respectively, whereas the Raman E2(high) peak FWHM value is about 23 cm-1. Decreasing intensity of silicon and carbon LVM peaks with increasing distance from the interface represents the reduction of their incorporation along the crystal length. EPMA analysis confirms the presence of low silicon concentration of 2 wt% in these crystals grown hetero-epitaxially on SiC.

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Growth of Lu2O3 and HfO2 Based High Melting Temperature Single Crystals by Indirect Heating Method Using Arc Plasma

Crystals ◽

10.3390/cryst10070619 ◽

2020 ◽

Vol 10 (7) ◽

pp. 619

Author(s):

Kyoung Jin Kim ◽

Kei Kamada ◽

Rikito Murakami ◽

Takahiko Horiai ◽

Shiori Ishikawa ◽

...

Keyword(s):

Single Crystals ◽

Arc Plasma ◽

High Melting ◽

High Melting Point ◽

Rocking Curve ◽

Heating Method ◽

Growth Method ◽

Transfer State ◽

Better Than ◽

Indirect Heating

A novel single-crystal growth method was developed, using arc plasma and metal melt, for a quick survey of high melting point materials. Single crystals of Yb-doped Lu2O3, Lu0.388Hf0.612O1.806, and Lu0.18Hf0.82O1.91, with melting points of 2460, 2900, and 2840 °C, respectively, were grown by an indirect heating method using arc plasma. We refer to this indirect heating growth method as the core heating (CH) method. The CH-grown Yb1%-doped Lu2O3 sample showed a full width at half maximum of 286 arcsec in the X-ray rocking curve. This value is better than the 393 arcsec obtained for the crystal grown by the micro-pulling-down (μ-PD) method. The Yb charge transfer state (CTS) emission was observed at 350 nm in the Yb1%-doped Lu2O3 and Lu0.18Hf0.82O1.91. In the case of the μ-PD method, using a rhenium (Re) crucible, absorption due to Re contamination and a resulting reduction in the Yb CTS emission were confirmed. However, contamination did not influence the properties observed in the crystals grown by the CH method.

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New Lanthanide Oxalato-nitrates Crystallized From Acidic Solutions

MRS Proceedings ◽

10.1557/proc-1265-aa04-05 ◽

2010 ◽

Vol 1265 ◽

Cited By ~ 2

Author(s):

Christelle Tamain ◽

Murielle Rivenet ◽

Bénédicte Arab-Chapelet ◽

Stéphane Grandjean ◽

Francis Abraham

Keyword(s):

Single Crystals ◽

Diethyl Oxalate ◽

X Ray Diffraction ◽

Experimental Conditions ◽

Acidic Solutions ◽

Counter Ions ◽

Monovalent Ions ◽

Growth Method ◽

Metal Oxalate

AbstractTo identify the various oxalates and oxalato-nitrates likely to form during the nuclear fuel reprocessing we study crystallization of such compounds by various methods (slow diffusion, hydrothermal syntheses, in situ oxalate syntheses …), in different conditions and in presence of monovalent ions. In a first stage, lanthanides are used as surrogates of the actinides (III) radioactive elements. This communication reviews various lanthanides (III) compounds obtained by crystallization from nitric acid solution containing hydrazinium ions. Diethyl oxalate was used as a precursor for oxalate ions. A careful adjustment of the experimental conditions allowed us to synthesize single crystals of nitrates, oxalato-nitrates and oxalates with various ligand/Ln(III) ratio and containing nitrates as ligands or as counter ions. In all the compounds hydrazinium ions are present as counter ions. The crystal growth method is described and the crystal structures, determined by X-ray diffraction from single crystals, are discussed in terms of metal-oxalate frameworks.

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Flux Method Growth of Large Size Group IV–V 2D GeP Single Crystals and Photoresponse Application

Crystals ◽

10.3390/cryst11030235 ◽

2021 ◽

Vol 11 (3) ◽

pp. 235

Author(s):

Shuqi Zhao ◽

Tongtong Yu ◽

Ziming Wang ◽

Shilei Wang ◽

Limei Wei ◽

...

Keyword(s):

Raman Spectroscopy ◽

Single Crystals ◽

High Performance ◽

Group Iv ◽

X Ray Diffraction ◽

High Quality ◽

Practical Applications ◽

Large Size ◽

Growth Method ◽

Polarized Raman

Two-dimensional (2D) materials driven by their unique electronic and optoelectronic properties have opened up possibilities for their various applications. The large and high-quality single crystals are essential to fabricate high-performance 2D devices for practical applications. Herein, IV-V 2D GeP single crystals with high-quality and large size of 20 × 15 × 5 mm3 were successfully grown by the Bi flux growth method. The crystalline quality of GeP was confirmed by high-resolution X-ray diffraction (HRXRD), Laue diffraction, electron probe microanalysis (EPMA) and Raman spectroscopy. Additionally, intrinsic anisotropic optical properties were investigated by angle-resolved polarized Raman spectroscopy (ARPRS) and transmission spectra in detail. Furthermore, we fabricated high-performance photodetectors based on GeP, presenting a relatively large photocurrent over 3 mA. More generally, our results will significantly contribute the GeP crystal to the wide optoelectronic applications.

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Numerical Analysis of Difficulties of Growing Large-Size Bulk β-Ga2O3 Single Crystals with the Czochralski Method

Crystals ◽

10.3390/cryst11010025 ◽

2020 ◽

Vol 11 (1) ◽

pp. 25

Author(s):

Xia Tang ◽

Botao Liu ◽

Yue Yu ◽

Sheng Liu ◽

Bing Gao

Keyword(s):

Crystal Growth ◽

Single Crystals ◽

Czochralski Method ◽

Liquid Interface ◽

Spiral Growth ◽

Growth Time ◽

Large Size ◽

Crystal Diameter ◽

Solid Liquid Interface ◽

Solid Liquid

The difficulties in growing large-size bulk β-Ga2O3 single crystals with the Czochralski method were numerically analyzed. The flow and temperature fields for crystals that were four and six inches in diameter were studied. When the crystal diameter is large and the crucible space becomes small, the flow field near the crystal edge becomes poorly controlled, which results in an unreasonable temperature field, which makes the interface velocity very sensitive to the phase boundary shape. The effect of seed rotation with increasing crystal diameter was also studied. With the increase in crystal diameter, the effect of seed rotation causes more uneven temperature distribution. The difficulty of growing large-size bulk β-Ga2O3 single crystals with the Czochralski method is caused by spiral growth. By using dynamic mesh technology to update the crystal growth interface, the calculation results show that the solid–liquid interface of the four-inch crystal is slightly convex and the center is slightly concave. With the increase of crystal growth time, the symmetry of cylindrical crystal will be broken, which will lead to spiral growth. The numerical results of the six-inch crystal show that the whole solid–liquid interface is concave and unstable, which is not conducive to crystal growth.

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Two-level growth of potassium niobate KNbO3 single crystals: a new growth method for ABO3-type materials

Journal of Crystal Growth ◽

10.1016/0022-0248(95)00909-4 ◽

1996 ◽

Vol 160 (3-4) ◽

pp. 296-304 ◽

Cited By ~ 5

Author(s):

H.C. Zeng ◽

T.C. Chong ◽

L.C. Lim ◽

H. Kumagai ◽

M. Hirano

Keyword(s):

Single Crystals ◽

Potassium Niobate ◽

Growth Method

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Growth of Bulk GaN Single Crystals by the Pressure-Controlled Solution Growth Method

Japanese Journal of Applied Physics ◽

10.1143/jjap.39.2394 ◽

2000 ◽

Vol 39 (Part 1, No. 4B) ◽

pp. 2394-2398 ◽

Cited By ~ 13

Author(s):

Takayuki Inoue ◽

Yoji Seki ◽

Osamu Oda ◽

Satoshi Kurai ◽

Yoichi Yamada ◽

...

Keyword(s):

Single Crystals ◽

Solution Growth ◽

Growth Method ◽

Bulk Gan ◽

Pressure Controlled

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Growth of oriented soft lead zirconate titanate single crystals via solid-state single crystal growth method

2021 IEEE International Symposium on Applications of Ferroelectrics (ISAF) ◽

10.1109/isaf51943.2021.9477389 ◽

2021 ◽

Author(s):

Honghui Wang ◽

Song Xia ◽

Tingting Wang ◽

Ming Ma ◽

Zhenrong Li

Keyword(s):

Crystal Growth ◽

Solid State ◽

Single Crystal ◽

Single Crystals ◽

Lead Zirconate Titanate ◽

Lead Zirconate ◽

Single Crystal Growth ◽

Zirconate Titanate ◽

Growth Method

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Effect of Excess PbO on the Kinetics of the Growth of PMNT Polycrystals by Templated Grain Growth Method

Materials Science Forum ◽

10.4028/www.scientific.net/msf.475-479.1137 ◽

2005 ◽

Vol 475-479 ◽

pp. 1137-1140

Author(s):

Lili Zhao ◽

Feng Gao ◽

Wei Min Wang ◽

Chang Sheng Tian

Keyword(s):

Grain Growth ◽

Templated Grain Growth ◽

Experimental Conditions ◽

Precipitation Mechanism ◽

Oriented Structure ◽

Diffusion Controlled ◽

The Matrix ◽

Growth Method ◽

Final Composition ◽

Kinetics Of

The oriented 0.67Pb (Mg1/3Nb2/3)O3-0.33PbTiO3 (PMNT) polycrystals were prepared by the conventional ceramic technique and the templated grain growth method adding excess PbO in the matrix. Kinetics of the development of oriented structure was investigated systemically. In the presence of PbO liquid phase, the oriented PMNT polycrystals mainly grow by the dissolution-precipitation mechanism. The diffusion is determined by the sintering temperature and the PbO-excess content in the matrix. The thickness of oriented PMNT polycrystals displays a t1/3 dependence, which is characteristic of diffusion-controlled growth. For the thicker oriented structure, 20% excess PbO in the PMNT matrix and 1150oC for 10h are the proper experimental conditions. Moreover, the addition of PbO in the matrix hardly affects the final composition of ceramic matrix.

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