Investigation of growth mechanisms of TSS-grown KLu(WO4)2 crystals by atomic force microscopy

Growth mechanisms on the {110} and {310} faces of KLu(WO4)2 crystals for the case of top-seeded solution growth technique have been investigated using ex situ atomic force microscopy (AFM). Both 2D nuclei and spiral hillocks are imaged simultaneously on the {110} surfaces. A special dislocation sources structure with the Burgers vectors perpendicular to the {110} crystal face of b=8 are discussed. The 2D nuclei with elementary-step height are distributed in the direction of the strong PBC [101], indicative of anisotropic surface diffusion or step edge energy. Straight step trains are observed on the {310} surfaces of KLuW and they move towards to [001] directions. It was confirmed that the growth proceeds by both screw dislocation sources and 2D nucleus on the {110} surfaces and by simple flow of steps on {310} surfaces.