Source/drain contact structures that exhibit low contact resistance and improved electromigration properties are provided. After forming a first contact conductor portion comprising a metal having a high resistance to electromigration such as tungsten at a bottom portion of source/drain contact trench to form direct contact with a source/drain region of a field effect transistor, a second contact conductor portion comprising a highly conductive metal such as copper or a copper alloy is formed over the first contact conductor portion.

Methods for integration of conformal barrier layers and Ru metal liners with Cu metallization in semiconductor manufacturing are described in several embodiments. According to one embodiment, the method includes providing a substrate containing a recessed feature, depositing a barrier layer in the recessed feature, depositing a Ru metal liner on the barrier layer, and exposing the substrate to an oxidation source gas to oxidize the barrier layer through the Ru metal liner. The method further includes filling the recessed feature with CuMn metal using an ionized physical vapor deposition (IPVD) process, heat-treating the substrate to diffuse Mn from the CuMn metal to the oxidized barrier layer, and reacting the diffused Mn with the oxidized barrier layer to form a Mn-containing diffusion barrier.

A method for forming an ion flow barrier between conductors includes forming a barrier material through a via in an interlevel dielectric layer and onto a first metal layer and recessing the barrier material to form a thickness of the barrier material on the first metal layer in the via, the thickness forming an ion flow barrier. A second metal layer is deposited in the via over the ion flow barrier such that, during operation, the ion flow barrier reduces ion flow between the first metal layer and the second metal layer while maintaining low resistance.

According to one embodiment, a method for manufacturing a semiconductor device is disclosed. The method includes forming a co-catalyst layer and catalyst layer above a surface of a semiconductor substrate. The co-catalyst layer and catalyst layer have fcc structure. The fcc structure is formed such that (111) face of the fcc structure is to be oriented parallel to the surface of the semiconductor substrate. The catalyst includes a portion which contacts the co-catalyst layer. The portion has the fcc structure. An exposed surface of the catalyst layer is planarized by oxidation and reduction treatments. A graphene layer is formed on the catalyst layer.

An opening is formed through a dielectric material layer to physically expose a top surface of a conductive material portion in, or over, a substrate. A metallic nitride liner is formed on a sidewall of the opening and on the top surface of the conductive material portion. A metallic adhesion layer including an alloy of copper and at least one transition metal that is not copper is formed on an inner sidewall of the metallic nitride liner. A copper fill material portion may be formed on an inner sidewall of the metallic adhesion layer. The metallic adhesion layer is thermally stable, and remains free of holes during subsequent thermal processes, which may include reflow of the copper fill material portion. An additional copper fill material portion may be optionally deposited after a reflow process.

An opening is formed through a dielectric material layer to physically expose a top surface of a conductive material portion in, or over, a substrate. A metallic nitride liner is formed on a sidewall of the opening and on the top surface of the conductive material portion. A metallic adhesion layer including an alloy of copper and at least one transition metal that is not copper is formed on an inner sidewall of the metallic nitride liner. A copper fill material portion may be formed on an inner sidewall of the metallic adhesion layer. The metallic adhesion layer is thermally stable, and remains free of holes during subsequent thermal processes, which may include reflow of the copper fill material portion. An additional copper fill material portion may be optionally deposited after a reflow process.

A semiconductor device includes an interconnect structure embedded in a first metallization layer comprising a dielectric material. The interconnect structure includes a first metal material. The semiconductor device includes a first liner structure embedded in the first metallization layer. The first liner structure is extended along one or more boundaries of the interconnect structure in the first metallization layer. The first liner structure includes a second metal material reacted with one or more dopants, the second metal material being different from the first metal material.

Methods of forming copper interconnects are described. A doped tantalum nitride layer formed on a copper layer on a substrate has a first amount of dopant. The doped tantalum nitride layer is exposed to a plasma comprising one or more of helium or neon to form a treated doped tantalum nitride layer with a decreased amount of dopant. Apparatus for performing the methods are also described.

The present application discloses a semiconductor device with adjustment layers and a method for fabricating the semiconductor device with the adjustment layers. The semiconductor device includes a substrate, an interconnection structure positioned on the substrate, a contact positioned penetrating the interconnection structure, and two adjustment layers positioned on sidewalls of the contact.

Ohmic contacts, including materials and processes for forming n-type ohmic contacts on n-type semiconductor substrates at low temperatures, are disclosed. Materials include reactant layers, n-type dopant layers, capping layers, and in some instances, adhesion layers. The capping layers can include metal layers and diffusion barrier layers. Ohmic contacts can be formed on n-type semiconductor substrates at temperatures between 150 and 250° C., and can resist degradation during operation.