ZrO2 is a potential candidate for the realization of 3D capacitors on silicon for future Systems-on-Chip. This paper reports on the deposition of ZrO2 thin films by metal-organic chemical vapor deposition on planar and 3D structures. Physico-chemical as well as electrical properties of the films are investigated. It is shown that the change of phase and microstructure of the film due to annealing at 900 degrees C under O-2 impacts directly on the electrical performance of the capacitors. Capacitance densities are 2 nF/mm(2) for planar capacitors and reach 8 nF/mm(2) for capacitors with pores etched in silicon with a 4:1 aspect ratio. (C) 2011 Elsevier B.V. All rights reserved.