NOVELTY - Fabricating three-dimensional structures (100) (S1) involves forming 3-dimentional (3-D) structure comprising first layer and array of pillars (115) with cavity regions between the pillars; filling cavity regions (120) with fill material, where fill material covers each segment; removing a first portion of fill material to produce exposed portion of segment; simultaneously depositing electrode onto fill material and each the exposed segment, thus forming conductive layer that provides common contact to each exposed segment; and depositing second electrode on first layer.    USE - For fabricating three-dimensional structures (claimed), for micro- and nano-electronics, useful in e.g. thermoelectrics, catalysts, sensors, including thermal neutron and radiation detectors, energy storage devices such as batteries and ultra-capacitors, solar cells, photonic and phononic crystals, image converters and intensifiers, acoustic transducers and smart, reconfigurable materials.    ADVANTAGE - The method enables high-yield, uniform and reliable conformal blanket coatings to be realized across the surfaces of such high-aspect ratio structures; enables high-quality conformal coatings to be realized by augmenting the planarization of a sacrificial layer (as above), with the formation of an array of self-aligned via-holes onto the respective pillar array. The result of this fabrication procedure is improved device reliability and yield. This processing technique also minimizes failure modes by etching via holes directly to the top of the underlying structure.    DETAILED DESCRIPTION - Fabricating three-dimensional structures (100) (S1) having conformal electrodes involves forming a 3-dimentional (3-D) structure comprising a first layer and an array of pillars (115) with cavity regions between the pillars, where each pillar of the pillars comprises a first end and a second end, where the first end is in contact with the first layer, where the first layer comprises only one of n material or p material, where each the pillar comprises an intrinsic material; forming a segment on the second end of each the pillar, where the segment comprises the p material if the first layer comprises the n material and where the segment comprises the n material if the first layer comprises the p material; filling the cavity regions (120) with a fill material, where the fill material covers each the segment; removing a first portion of the fill material to produce an exposed portion of the segment; simultaneously depositing an electrode onto the fill material and each the exposed segment, thus forming a conductive layer that provides a common contact to each the exposed segment; and depositing a second electrode on the first layer. An INDEPENDENT CLAIM is included for apparatus comprising the 3-dimentional (3-D) structure (S1).    DESCRIPTION OF DRAWING(S) - The figure shows cross-sectional view of three-dimensional structures.    Three-dimensional structures (100)    Substrate (110)    Array of pillars (115)    Cavity regions (120)