Method for manufacturing a capacitive device comprising the following steps: i) provide a substrate comprising: - a first area made of a first material and/or having a first texture, - a second area made of a second material and/or having a second texture, - a third area made of a third material and/or having a third texture, the first material being different from the third material and/or the first texture being different from the third texture, the first material may be identical to or different from the second material and/or the first texture may be identical to or different from the second texture, ii) make nanopillars grow over the substrate, with which a nanopillar layer is obtained locally having different densities, the nanopillars at the first area having a first density, the nanopillars at the second area having a second density, the nanopillars at the third area having a third density, the first density and the second density being lower than the third density, the first density may be identical to or different from the second density, iii) deposit an insulating layer over the nanopillar layer, the insulating layer covering the nanopillars in a conformal and continuous manner at least at the first area, iv) deposit a conductive layer, over the nanopillar layer, the conductive layer covering the insulating layer in a conformal and continuous manner at least at the first area, with which a capacitive stack is formed at the first area, the capacitive stack comprising the insulating layer and the conductive layer. i) provide a substrate comprising: - a first area made of a first material and/or having a first texture, - a second area made of a second material and/or having a second texture, - a third area made of a third material and/or having a third texture, the first material being different from the third material and/or the first texture being different from the third texture, the first material may be identical to or different from the second material and/or the first texture may be identical to or different from the second texture, - a first area made of a first material and/or having a first texture, - a second area made of a second material and/or having a second texture, - a third area made of a third material and/or having a third texture, the first material being different from the third material and/or the first texture being different from the third texture, ii) make nanopillars grow over the substrate, with which a nanopillar layer is obtained locally having different densities, the nanopillars at the first area having a first density, the nanopillars at the second area having a second density, the nanopillars at the third area having a third density, the first density and the second density being lower than the third density, the first density may be identical to or different from the second density, iii) deposit an insulating layer over the nanopillar layer, the insulating layer covering the nanopillars in a conformal and continuous manner at least at the first area, iv) deposit a conductive layer, over the nanopillar layer, the conductive layer covering the insulating layer in a conformal and continuous manner at least at the first area, with which a capacitive stack is formed at the first area, the capacitive stack comprising the insulating layer and the conductive layer.