The present application discloses a method for fabricating a conductive layer stack. The method includes forming an intervening layer on an under-layer; and forming a filler layer on the intervening layer, wherein the filler layer comprises tungsten. The intervening layer comprises tungsten silicide and a thickness of the intervening layer is greater than 4.1 nm. The under-layer comprises titanium nitride and comprises a columnar grain structure.

The present application discloses a conductive layer stack, a semiconductor device and methods for fabricating the conductive layer stack and the semiconductor device. The conductive layer stack includes an intervening layer comprising tungsten silicide and positioned on an under-layer; a filler layer comprising tungsten and positioned on the intervening layer. The under-layer comprises titanium nitride and comprises a columnar grain structure. A thickness of the intervening layer is greater than about 4.1 nm.

In one example, an electroplating system comprises a first bath reservoir, a second bath reservoir, a clamp, a first anode in the first bath reservoir, a second anode in the second bath reservoir, and a direct current power supply. The first bath reservoir contains a first electrolyte solution that includes an alkaline copper-complexed solution. The second bath reservoir contains a second electrolyte solution that includes an acidic copper plating solution. The direct current power supply generates a first direct current between the clamp and the first anode to electroplate a first copper layer on the cobalt layer of the wafer submerged in the first electrolyte solution. The direct current power supply then generates a second direct current between the clamp and the second anode to electroplate a second copper layer on the first copper layer of the wafer submerged in the second electrolyte solution.

A barrier layer is formed in a portion of a thickness of sidewalls in a recess prior to formation of an interconnect structure in the recess. The barrier layer is formed in the portion of the thickness of the sidewalls by a plasma-based deposition operation, in which a precursor reacts with a silicon-rich surface to form the barrier layer. The barrier layer is formed in the portion of the thickness of the sidewalls in that the precursor consumes a portion of the silicon-rich surface of the sidewalls as a result of the plasma treatment. This enables the barrier layer to be formed in a manner in which the cross-sectional width reduction in the recess from the barrier layer is minimized while enabling the barrier layer to be used to promote adhesion in the recess.

A semiconductor structure with an improved metal structure is described. The semiconductor structure can include a substrate having an upper surface, an interconnect layer over the upper surface, and an additional structure deposited over the interconnect layer. The interconnect layer can include a patterned seed layer over the substrate, at least two metal lines over the seed layer, and a dielectric material between adjacent metal lines. A barrier layer can be deposited over the at least two metal lines. Methods of making the semiconductor structures are also described.

A semiconductor structure with an improved metal structure is described. The semiconductor structure can include a substrate having an upper surface, an interconnect layer over the upper surface, and an additional structure deposited over the interconnect layer. The interconnect layer can include a patterned seed layer over the substrate, at least two metal lines over the seed layer, and a dielectric material between adjacent metal lines. A barrier layer can be deposited over the at least two metal lines. Methods of making the semiconductor structures are also described.

Embodiments of the present disclosure relate to methods of fabricating conductive features to prevent metal extrusion. Particularly, the conductive feature includes a control layer to reduce grain size of a metal containing layer, thus obtaining a robust structure to decrease extrusion defects. In some embodiments, the control layer is formed between a barrier layer and the conductive feature. In some embodiments, the control layer is formed by adding a control element, such as oxygen, to an upper portion of the barrier layer.

A structure and a method for fabricating interconnections for an integrated circuit device are described. The method forms a metal interconnection pattern having a first barrier layer and a copper layer in a set of trenches in a first dielectric layer over a substrate. In a selected area, the first dielectric layer is removed to so that the first barrier layer can be removed at the exposed vertical surfaces. A thin second barrier layer is deposited over the exposed vertical surfaces of the first copper layer. A structure includes a first feature formed in a first dielectric layer which has a first barrier layer disposed on vertical surfaces of the first dielectric layer and surrounds opposing vertical surfaces and a bottom surface of a copper layer. The structure also includes a second feature formed in a second dielectric layer which has a second barrier layer disposed on vertical surfaces of the second dielectric layer and two vertical surfaces of the copper layer and a bottom surface of the first copper layer is disposed over the first barrier layer.

A semiconductor device includes a peripheral circuit region comprising a first substrate, circuit elements on the first substrate, a first insulating layer covering the circuit elements, and a contact plug passing through the first insulating layer and disposed to be connected to the first substrate; and a memory cell region comprising a second substrate, gate electrodes on the second substrate and stacked in a vertical direction, and channel structures passing through the gate electrodes, wherein the contact plug comprises a metal silicide layer disposed to contact the first substrate and having a first thickness, a first metal nitride layer on the metal silicide layer to contact the metal silicide layer and having a second thickness, greater than the first thickness, a second metal nitride layer on the first metal nitride layer, and a conductive layer on the second metal nitride layer.

Various embodiments of the present disclosure are directed towards an integrated circuit (IC) in which cavities separate wires of an interconnect structure. For example, a conductive feature overlies a substrate, and an intermetal dielectric (IMD) layer overlies the conductive feature. A first wire and a second wire neighbor in the IMD layer and respectively have a first sidewall and a second sidewall that face each other while being separated from each other by the IMD layer. Further, the first wire overlies and borders the conductive feature. A first cavity and a second cavity further separate the first and second sidewalls from each other. The first cavity separates the first sidewall from the IMD layer, and the second cavity separates the second sidewall from the IMD layer. The cavities reduce parasitic capacitance between the first and second wires and hence resistance-capacitance (RC) delay that degrades IC performance.