Study of the specific features of single-crystal boron microstructure

• Published in: Crystallography reports Vol. 62; no. 5; pp. 692 - 702
• Main Authors: Blagov, A. E., Vasil’ev, A. L., Dmitriev, V. P., Ivanova, A. G., Kulikov, A. G., Marchenkov, N. V., Popov, P. A., Presnyakov, M. Yu, Prosekov, P. A., Pisarevskii, Yu. V., Targonskii, A. V., Chernaya, T. S., Chernyshov, D. Yu
• Format: Journal Article
• Language: English
• Published: Moscow Pleiades Publishing 01-09-2017; Springer Nature B.V
• Subjects: Aberration; Atomic structure; BORON; Crystal defects; CRYSTAL GROWTH; Crystal structure; CRYSTALLOGRAPHY; Crystallography and Scattering Methods; Diffraction; Diffraction and Scattering of Ionizing Radiations; DISLOCATIONS; Energy transmission; Faults; Floating structures; GEOMETRICAL ABERRATIONS; IMPURITIES; MATERIALS SCIENCE; MICROANALYSIS; MICROSTRUCTURE; MONOCRYSTALS; NEUTRON DIFFRACTION; Nuclear electric power generation; Physics; Physics and Astronomy; Pole figures; Scanning transmission electron microscopy; Single crystals; STACKING FAULTS; SYNCHROTRON RADIATION; TEMPERATURE DEPENDENCE; TEMPERATURE RANGE 0013-0065 K; TEMPERATURE RANGE 0065-0273 K; THERMAL CONDUCTIVITY; TRANSMISSION ELECTRON MICROSCOPY; X-RAY DIFFRACTION; X-rays
• ISSN: 1063-7745; 1562-689X
• DOI: 10.1134/S1063774517050030

A complex study of the structure of β-boron single crystal grown by the floating-zone method, with sizes significantly exceeding the analogs known in the literature, has been performed. The study includes X-ray diffraction analysis and X-ray diffractometry (measurement of pole figures and rocking curves), performed on both laboratory and synchrotron sources; atomic-resolution scanning transmission electron microscopy with spherical aberration correction; and energy-dispersive microanalysis. X-ray diffraction analysis using synchrotron radiation has been used to refine the β-boron structure and find impurity Si atoms. The relative variations in the unit-cell parameters
a
and
c
for the crystal bulk are found to be δ
a
/
a
≈ 0.4 and δ
c
/
c
≈ 0.1%. X-ray diffractometry has revealed that the single-crystal growth axis coincides with the [
2
2
¯
013
] crystallographic axis and makes an angle of 21.12° with the [0001] threefold axis. Electron microscopy data have confirmed that the sample under study is a β-boron crystal, which may contain 0.3–0.4 at % Si as an impurity. Planar defects (stacking faults and dislocations) are found. The results of additional measurements of the temperature dependence of the thermal conductivity of the crystal in the range of 50–300 K are indicative of its high structural quality.