Abstract: A method for manufacturing circuit structures integrated in a semiconductor substrate that includes regions, in particular isolation regions, includes the steps of:—depositing a conductive layer to be patterned onto the semiconductor substrate;—forming a first mask of a first material on the conductive layer;—forming a second mask made of a second material that is different from the first and provided with first openings of a first size having spacers formed on their sidewalls to uncover portions of the first mask having a second width which is smaller than the first;—partly etching away the conductive layer through the first and second masks such to leave grooves of the second width;—removing the second mask and the spacers; and—etching the grooves through the first mask to uncover the regions provided in the substrate and form conductive lines.

Abstract: A process for forming a dielectric isolation structure on a silicon substrate includes forming at least one trench in the substrate, performing a high-temperature treatment in an oxidizing environment to form a first liner layer of silicon dioxide on the walls and the bottom of the trench, and performing a silicon dioxide deposition treatment to form a second liner layer on the first liner layer. A silicon nitride deposition treatment is also performed to form a third liner layer on the second liner layer. The trench is filled with isolating material.

Abstract: A method for manufacturing circuit structures integrated in a semiconductor substrate that includes regions, in particular isolation regions, includes the steps of:—depositing a conductive layer to be patterned onto the semiconductor substrate;—forming a first mask of a first material on the conductive layer;—forming a second mask made of a second material that is different from the first and provided with first openings of a first size having spacers formed on their sidewalls to uncover portions of the first mask having a second width which is smaller than the first;—partly etching away the conductive layer through the first and second masks such to leave grooves of the second width;—removing the second mask and the spacers; and—etching the grooves through the first mask to uncover the regions provided in the substrate and form conductive lines.

Abstract: A process for etching a dielectric layer, including the steps of forming, over the dielectric layer, a layer of polysilicon, forming over the layer of polysilicon a photoresist mask layer, etching the layer of polysilicon using the photoresist mask layer as an etching mask for selectively removing the layer of polysilicon, removing the photoresist mask layer from over the layer of polysilicon, etching the dielectric layer using the layer of polysilicon as a mask. Subsequently, the layer of polysilicon is converted into a layer of a transition metal silicide, and the layer of transition metal silicide is etched for selectively removing the latter from over the dielectric layer.