Techniques for incorporating nanotechnology into decoupling capacitor designs are provided. In one aspect, a decoupling capacitor is provided. The decoupling capacitor comprises a first electrode; an intermediate layer adjacent to the first electrode having a plurality of nanochannels therein; a conformal dielectric layer formed over the intermediate layer and lining the nanochannels; and a second electrode at least a portion of which is formed from an array of nanopillars that fill the nanochannels in the intermediate layer. Methods for fabricating the decoupling capacitor are also provided, as are semiconductor devices incorporating the decoupling capacitor design.