Abstract: A polycrystalline dielectric layer is formed wherein the dielectric layer comprises a first dielectric material containing an oxide or nitride and a second material contributing to less than 1% in weight to the dielectric layer, forming a non-conductive oxide or nitride having an enthalpy lower than the enthalpy of the first dielectric material such that a leakage current along grain boundaries of the first dielectric material is reduced.

Abstract: A semiconductor substrate is provided comprising a plurality of contact pads arranged on a horizontal surface of the semiconductor substrate. Pillars of a first sacrificial material are formed on the contact pads. A first dielectric layer is deposited thus covering at least said pillars. A first conductive layer is deposited between said pillars covered with the first dielectric layer. The pillars are removed thus providing trenches in the first conductive layer having walls covered with the dielectric layer. A second conductive layer is deposited on the first dielectric layer in the trench. A second dielectric layer is deposited such that at least the second conductive layer in the trench is covered by the second dielectric layer. A third conductive layer is deposited on the second dielectric layer.