Journal of Crystal Growth, Vol.391, 7-12, 2014
Nanoscopic investigations on the surface topography, defect-substructure, dislocations and micromorphology of surfaces of BaxSr1-x(NO3)(2) mixed crystals
Experimental investigations on the defect-substructure, dislocations and micromorphological features of the surfaces of mixed crystals of Ba chi Sr1-chi(NO3)(2) have been reported. Variations in the micromorphological features have been studied over a whole composition range. Morphology of these crystal surfaces, as investigated by Atomic Force Microscopy (AFM), is found to depend mainly on the degree of supersaturation, concentration of Ba-2 /Sr2+ ions in solution and growth temperature. Observations of growth spiral in concurrence with height of hillocks revealed the existence of screw dislocations that led to the proposition of two dimensional nucleation of crystal growth process. Observation of coalescence of neighbouring growth spirals displays the Frank-Read mechanism in the growth process. (C) 2014 Elsevier B.V. All rights rescrvect