Abstract: A method includes forming a dielectric layer over an epitaxial source/drain region. An opening is formed in the dielectric layer. The opening exposes a portion of the epitaxial source/drain region. A barrier layer is formed on a sidewall and a bottom of the opening. An oxidation process is performing on the sidewall and the bottom of the opening. The oxidation process transforms a portion of the barrier layer into an oxidized barrier layer and transforms a portion of the dielectric layer adjacent to the oxidized barrier layer into a liner layer. The oxidized barrier layer is removed. The opening is filled with a conductive material in a bottom-up manner. The conductive material is in physical contact with the liner layer.

Abstract: A semiconductor structure includes a source/drain feature in the semiconductor layer. The semiconductor structure includes a dielectric layer over the source/drain feature. The semiconductor structure includes a silicide layer over the source/drain feature. The semiconductor structure includes a barrier layer over the silicide layer. The semiconductor structure includes a seed layer over the barrier layer. The semiconductor structure includes a metal layer between a sidewall of the seed layer and a sidewall of the dielectric layer, a sidewall of each of the silicide layer, the barrier layer, and the metal layer directly contacting the sidewall of the dielectric layer. The semiconductor structure includes a source/drain contact over the seed layer.

Abstract: A method includes forming a dielectric layer over an epitaxial source/drain region. An opening is formed in the dielectric layer. The opening exposes a portion of the epitaxial source/drain region. A barrier layer is formed on a sidewall and a bottom of the opening. An oxidation process is performing on the sidewall and the bottom of the opening. The oxidation process transforms a portion of the barrier layer into an oxidized barrier layer and transforms a portion of the dielectric layer adjacent to the oxidized barrier layer into a liner layer. The oxidized barrier layer is removed. The opening is filled with a conductive material in a bottom-up manner. The conductive material is in physical contact with the liner layer.

Abstract: A pre-cleaning technique described herein may be used to remove native oxides and/or other contaminants from a semiconductor device in a manner in which the likelihood of chopping, clipping, and/or sidewall spacer thickness reduction is reduced. As described herein, a protection layer is formed on a capping layer over a gate structure of a transistor. A pre-cleaning operation is then performed to remove native oxides from the top surface of a source/drain region of the transistor. In the pre-cleaning operation, the protection layer is consumed instead of the material of the capping layer. In this way, the use of the protection layer reduces the likelihood of removal of material from the capping layer and/or reduces the amount of material that is removed from the capping layer during the pre-cleaning operation.

Abstract: A method includes forming a dielectric layer over a source/drain region. An opening is formed in the dielectric layer. The opening exposes a portion of the source/drain region. A conductive liner is formed on sidewalls and a bottom of the opening. A surface modification process is performed on an exposed surface of the conductive liner. The surface modification process forms a surface coating layer over the conductive liner. The surface coating layer is removed to expose the conductive liner. The conductive liner is removed from the sidewalls of the opening. The opening is filled with a conductive material in a bottom-up manner. The conductive material is in physical contact with a remaining portion of the conductive liner and the dielectric layer.

Abstract: A method includes forming a dielectric layer over an epitaxial source/drain region. An opening is formed in the dielectric layer. The opening exposes a portion of the epitaxial source/drain region. A barrier layer is formed on a sidewall and a bottom of the opening. An oxidation process is performing on the sidewall and the bottom of the opening. The oxidation process transforms a portion of the barrier layer into an oxidized barrier layer and transforms a portion of the dielectric layer adjacent to the oxidized barrier layer into a liner layer. The oxidized barrier layer is removed. The opening is filled with a conductive material in a bottom-up manner. The conductive material is in physical contact with the liner layer.