Devices having voids are producible by employing an electrochemical corrosion process. For example, an electrically conductive region is formed to have a surrounding chemically distinct region. Such formation is possible through conventional semiconductor processing techniques such as a copper damascene process. The surrounded conducting material is configured to be in electrical communication with a charge separation structure. The electrically conducting region is contacted with a fluid electrolyte and electromagnetic radiation is made to illuminate the charge separation region to induce separation of electrons and holes. The resulting separated charges are used to drive an electrochemical corrosion process at the conductive material/electrolyte interface resulting in the removal of at least a portion of the electrically conducting material. The induced corrosion leaves a void that is useful, for example, as a highly effective dielectric in integrated circuits, functions to allow component separation such as gear separation in microelectromechanical devices or produces long cavities useful for material separation analogous to the distillation columns used in liquid chromatography.