High aspect ratio metal microstructures may be prepared by a method involving (i) forming a layer of a photoresist on a substrate; (ii) exposing the layer to actinic radiation in an imagewise manner and developing the exposed layer to obtain a surface which contains regions having no remaining photoresist and regions covered with photoresist; (iii) metallizing the surface to form a layer of metal on the region of the surface having no remaining photoresist and on the sides of the regions of photoresist remaining on the surface; and (iv) optionally, stripping the photoresist remaining on the surface. Such microstructures are useful as electron emitters, anisotropic high dielectric interconnects, masks for x-ray photolithography, carriers for the controlled release of active agents, and ultramicroelectrode arrays.