TEMPERATURE-DEPENDENCE OF X-RAY TOPOGRAPHIC IMAGES TAKEN AROUND INDENTATIONS OF SI SINGLE-CRYSTALS

This paper describes how X-ray topographic images taken around indentations are affected by temperature. Vickers indentations were made on the (111) surface of Si single crystals. In the low-temperature range (0-400 degrees C), the images resemble the number ''8'' and show a twofold symmetry. On the other hand, they show a threefold symmetry, similarly to a nest of triangles, in the elevated temperature range (higher than 500 degrees C). The difference in the topographic images reflects the difference in the mechanisms of deformation by indentations. It was concluded that the change of the images with temperature rise was attributed to the relative increase in plastic deformation in a microscopic sense rather than elastic deformation.