Lattice-plane curvature and small-angle grain boundaries in SiC bulk crystals

Beitrag in einer Fachzeitschrift

Details zur Publikation

Autor(en): Hock R
Zeitschrift: Journal of Applied Crystallography
Jahr der Veröffentlichung: 2006
Band: 39
Seitenbereich: 17-23
ISSN: 0021-8898


SiC crystals grown by the physical vapour transport process along the [001] direction show a curvature of the crystal growth front in correspondence with the shape of the isotherms. A large radius for the curvature of the isotherms enhances the formation of an extended facet. Under the facet, the lattice planes are flat with a high crystal quality as expressed by rocking-curve half widths of 0.022 degrees. In the non-faceted region, the lattice planes become bent, following the shape of the isotherms with a radius of typically 0.5 to 0.8 m and an increased rocking-curve half width of 0.3 degrees. A reduction of the growth rate from 300 mu m h(-1) to 70 mu m h(-1) does not affect this behaviour significantly. The lattice-plane curvature and the development of the facet are predominantly affected by the shape of the isotherms. For crystals grown in the [015] direction, the lattice planes adjust only in a one-dimensional manner to the isotherms. In all cases, the lattice-plane curvature results from the formation of a high density of small-angle grain boundaries. They are generated by the condensation of dislocations with Burgers vectors in the ab plane.

FAU-Autoren / FAU-Herausgeber

Hock, Rainer Prof. Dr.
Professur für Kristallographie und Strukturphysik

Zuletzt aktualisiert 2018-07-08 um 23:23