Interconnect structure for semiconductor device and related methods

A method of forming an interconnect structure, comprising:

• forming a trench through one or more dielectric layers, which are on a contact layer made of copper, so that a sidewall surface of the trench is formed by the one or more dielectric layers and a bottom surface of the trench is formed by a portion of the contact layer, wherein the copper on the bottom surface of the trench is a first oxidation state comprising at least of Cu(0) and Cu(I);
• chemically changing an oxidation state of the copper on the bottom surface of the trench from the first oxidation state to a second oxidation state, which is Cu(II),
• then forming a blocking layer comprising blocking molecules each comprising (a) a hydrophobic end group, (b) an electron rich head group and (c) a linker between the hydrophobic end group and the electron rich head group on the copper in the second oxidation state on the bottom surface of the trench;
• and
• depositing by atomic layer deposition a layer of TaN in the trench, wherein a thickness of the deposited insulating material on the sidewall surface of the trench is greater than a thickness of the deposited insulating material on the bottom surface of the trench.

A method of forming an interconnect structure, comprising:

• forming a trench through one or more dielectric layers, which are on a contact layer made of a metal, so that a sidewall surface of the trench is formed by the one or more dielectric layers and a bottom surface of the trench is formed by a portion of the contact layer, the bottom surface of the formed trench has the metal in a first oxidation state;
• chemically changing an oxidation state of the metal on the bottom surface of the trench from a first oxidation state to a second oxidation state, which is a more oxidized state than the first oxidation state;
• then forming a blocking layer comprising blocking molecules each comprising (a) a hydrophobic end group, (b) an electron rich head group and (c) a linker between the hydrophobic end group and the electron rich head group on the metal in the second oxidation state on the bottom surface of the trench, wherein the formed blocking layer formed on the metal in the second oxidation state is more stable than an otherwise identical blocking layer formed on the metal in the first oxidation state;
• and
• depositing a layer of an insulating material in the trench, wherein a thickness of the deposited insulating material on the sidewall surface of the trench is greater than a thickness of the deposited insulating material on the bottom surface of the trench.