Abstract
Growth of crystals from solutions were investigated by means of in situ observation methods, so that the formation of defects or growth striations can be investigated in relation to the degree of supersaturations and the mode of convection or flows. It was confirmed that unstable convection plumes start to develop at a critical supersaturation, 〜0.5%, around a growing Barium Nitrate crystal in an aqueous solution, which results in the large growth rate dispersion, >40%. It was also confirmed that due to the higher supersaturation at the surface very adjacent, <0.1 mm to the edge of a crystal, growth rate of a spiral hillock is accelerated nearly twice by generating the steps with double step density, even in a running solution. The acceleration was found to cease wheh the spiral centre relatively moves, being away, >0.1 mm, from the edge of the crystal as the crystal grows larger.
