Template-directed convective assembly of three-dimensional face-centered-cubic colloidal crystals

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Zhang J, Alsayed A, Lin KH, Sanyal S, Zhang F, Pao WJ, Balagurusamy VSK, Heiney PA, Yodh AG

Abstract:
We demonstrate that square two-dimensional grating templates can drive the growth of three-dimensional, face-centered-cubic (fcc) colloidal crystals by convective assembly. The square symmetry [i.e., (100) planes parallel to the substrate] of the underlying template was transferred to the colloidal crystal and maintained throughout its growth of similar to50 layers. We characterized crystals grown on flat and on templated substrates using electron microscopy and small-angle x-ray scattering (SAXS). SAXS measurements of the templated samples clearly show fourfold diffraction patterns that arise from fcc domains without stacking faults. (C) 2002 American Institute of Physics.