Quality of KDP crystals grown on point seeds by a novel rapid growth method

Structural perfection of KDP single crystals grown on point seeds by a rapid growth method has been studied by selective etching, UV spectroscopy, x-ray topography, a conoscopic method (to assess anomalous birefringence), rocking-curve analysis, and resistivity measurements. Etching results indicate that the dipyramid growth sectors are less homogeneous. The zonal structure is more pronounced in the peripheral parts of the crystals, that is, in the final stages of rapid growth. In spite of the sectorial and zonal inhomogeneities, the crystals are superior in quality to those prepared by other rapid growth methods.