XXXIX. Further observations of growth patterns on silicon carbide (Si-C) crystals

Abstract

This paper reports further observations of growth patterns on silicon carbide crystal faces using techniques previously described. In addition to the simple types of spirals in which the step height was shown to be equal to the height of an x-ray unit cell, spirals originating from dislocations of multiple strength, the step height being a multiple of the height of an x-ray unit cell, are reported. More complex geometrical growth patterns of groups of dislocations are illustrated. The conditions for the interaction of growth fronts issuing from a number of dislocations are discussed and shapes of the loci of points of intersection of such growth fronts are calculated and illustrated. It is observed that in any one region of the crystal, the screw dislocations are not only predominantly of the same sign but have also the same strength.