IUCr journals

Micropipe-induced birefringence in 6H silicon carbide

J. Appl. Cryst. (2010). 43, 122–133 (doi.org/10.1107/S0021889809043957)

[Birefringence from a micropipe] Experimental (left) and simulated (right) birefringence image of a micropipe from a 6H-SiC wafer.

The refractive index is a function of materials strain, and observing the birefringence around dislocations may reveal useful information. The dislocation core is in the range of angstroms, but the stress field can extend over tens of micrometers and becomes accessible to optical microscopy. We showed that the birefringence of well known defects such as silicon carbide micropipes can be put on a quantitative footing, and we were able to identify and fully reproduce the birefringent patterns. This technique is cheaper than transmission electron microscopy or X-ray topography.

T. Ouisse, D. Chaussende and L. Auvray