Abstract
Self-assembly of colloidal spheres onto patterned (e.g., lithographically modified) substrates is a promising approach to prepare complex three-dimensional (3D) geometries (e.g., assemble colloidal spheres into square pyramidal shapes) that cannot be produced by self-assembly of colloidal spheres on flat substrates. Generally self-assembly alone is restricted to the formation of close-packed two-dimensional (2D) and 3D arrays of colloidal particles and does not lead to more complex lattice types and geometries. A certain degree of control over colloidal self-assembly has been achieved through external electric or intense optical fields and by manipulating the interaction potential. Here, we demonstrate a simple scheme that combines two self-assembly steps and electrochemical deposition to produce patterns of ordered arrays of spheres with controlled sparine and eventually isolated metallic arrays of spherical cavities.