An integrated circuit structure includes a first interconnect layer including a first dielectric material. The first dielectric material has a first recess therein, the first recess having a first opening. The integrated circuit structure further includes a second interconnect layer above the first interconnect layer. The second interconnect layer includes a second dielectric material that has a second recess therein. The second recess has a second opening. In an example, at least a portion of the first opening of the first recess abuts and overlaps with at least a portion of the second opening of the second recess. In an example, a continuous conformal layer is on walls of the first and second recesses, and a continuous body of conductive material is within the first and second recesses.

A process includes forming, over a dielectric layer, a hardmask stack including a first layer below a second layer below a third layer below a fourth layer. The first and third layers include a different hardmask material from the second and fourth layers. A trench pattern including sidewall spacer structures is formed over the hardmask stack. The fourth layer is etched in a first region. The fourth and third layers are etched in a second region. The fourth and third layers are etched in a third region. The fourth layer is etched in a fourth region. The second and first layers are etched in the second and third regions. The third layer is etched in the first and fourth regions. In the dielectric layer, trenches are formed in the first and fourth regions, and via openings, deeper than the trenches, are formed in the second and third regions.

The present disclosure provides a semiconductor structure. The semiconductor structure includes: a substrate; a transistor on the substrate; a first dielectric layer over the transistor; a second dielectric layer over the first dielectric layer; a barrier layer extending from the second dielectric layer to the first dielectric layer; and a conductive structure separated from the second dielectric layer and the first dielectric layer by the barrier layer. The barrier layer includes: a first layer, including titanium or tantalum along inner sidewalls of the first dielectric layer and the second dielectric layer; a second layer, being an oxide of titanium or tantalum and over the first layer; and a third layer, including cobalt and over the second layer.

A method of manufacturing a semiconductor device includes depositing a dielectric layer over a substrate, performing a first patterning to form an opening in the dielectric layer, and depositing an oxide film over and contacting the dielectric layer and within the opening in the dielectric layer. The oxide film is formed from multiple precursors that are free of O.sub.2, and depositing the oxide film includes forming a plasma of a first precursor of the multiple precursors.