Fluid flow effects on crystalline perfection

Optimum solidification parameters for the production of highly perfect copper crystals by Czochralski growth are sought along with the documentation of crystal imperfections under various growth conditions. X-ray techniques which do not in their application produce defects and which allow the characterization of imperfections in single crystals are chosen to assess crystal perfection. The X-ray techniques employed ranged from ordinary Laue photography through Borrmann topography to double-crystal scanning diffractometry, thus allowing crystals with a wide variation in perfection to be studied. As a set of controllable solidification parameters, the rotation of the seed and of the melt and the diameter of the bottleneck are chosen. X-ray diffraction topographs are analyzed along with the data obtained from rocking curve measurements. Tables of growth conditions and quantitative data of rocking curve widths are presented.