Study of micropipe structure in SiC by x-ray phase contrast imaging

Phase contrast images of dislocation micropipe in SiC crystal are experimentally studied at various distances from the sample using synchrotron white beam. Computer simulation of these images enabled us to understand the peculiarities of image formation and measure the diameter of the micropipe. The phase contrast imaging of micropipes without monochromator is explained by the absorption of x rays in a thick (490 mu m) SiC crystal, effectively forming a high brilliance radiation spectrum with a pronounced maximum at 16 keV. (C) 2007 American Institute of Physics.