The growth of dendritic web material was studied by using X-ray diffraction topography to visualize the dislocations within. The resultant analysis of dislocation reactions provided information on the mechanisms which were involved in the formation of dislocation networks in the material. The present results were consistent with the introduction of Lomer dislocations, into dendritic web material, from reactions between 2 types of dislocation which were generated by thermal stresses. One type was trapped at the twin boundaries, while the other type was not. Although the web was thin, the configurations of the defects on the 2 sides of the twins were not the same. The existence of large stacking faults was a consequence of the stiffness of the stair rod at the Lomer dislocations, plus viscoplastic flow at high temperatures during growth or annealing. The double-contrast of the dislocation lines in synchrotron radiation white-beam topographs permitted a more rapid identification of the nature of dislocation lines along the growth direction.

Dislocations in Dendritic Web Silicon S.L.Morelhão, J.Härtwig, D.L.Meier: Journal of Crystal Growth, 2000, 213[3-4], 288-98