Low-resistance copper interconnects

A device, comprising:

• a single damascene structure included in a dielectric layer of the device and comprising a copper (Cu) layer;
• a ruthenium (Ru) liner between the single damascene structure and the dielectric layer,
• wherein the ruthenium liner is in contact with the copper layer on sidewalls of the single damascene structure, is in contact with the copper layer on a bottom surface of the single damascene structure, and is in contact with a contact plug below the single damascene structure, and
• wherein the contact plug is included in another dielectric layer of the device;
• a tantalum nitride (TaN) film between the ruthenium liner and the dielectric layer on sidewalls of the ruthenium liner,
• wherein the tantalum nitride film is in contact with the dielectric layer and the sidewalls of the ruthenium liner;
• a metallization layer, below the contact plug, that includes a metal gate of the device;
• another copper layer in the contact plug;
• another ruthenium liner between the other copper layer and the other dielectric layer,
• wherein the other ruthenium liner is in contact with the other copper layer on sidewalls of the other copper layer and on a bottommost surface of the other copper layer, and is in physical contact with the metallization layer, and
• wherein the other ruthenium liner is between the bottommost surface of the other copper layer and the metallization layer;
• and
• a ruthenium oxide (RuOx) film between the other ruthenium liner and the other dielectric layer on sidewalls of the other ruthenium liner,
• wherein the ruthenium oxide film is in contact with the other dielectric layer, is in contact with the sidewalls of the other ruthenium liner, and is out of physical contact with the metallization layer,
• wherein a portion of the ruthenium oxide film is disposed on top of and covers part of an upper portion of the other ruthenium liner, and
• wherein a lower portion of the other ruthenium liner is under the upper portion of the other ruthenium liner and is in physical contact with the metallization layer.

A device, comprising:

• a structure, included in a dielectric layer of the device, comprising a copper (Cu) layer;
• a metallization layer, below the structure, that includes a metal gate of the device;
• a ruthenium (Ru) liner between the copper layer and the dielectric layer,
• wherein the ruthenium liner is in contact with the copper layer on sidewalls of the copper layer, is in contact with the copper layer on a bottommost surface of the copper layer, and is in physical contact with the metallization layer, and
• wherein the ruthenium liner is between the bottommost surface of the copper layer and the metallization layer;
• and
• a film between the ruthenium liner and the dielectric layer on sidewalls of the ruthenium liner,
• wherein the film is in contact with the dielectric layer, is in contact with the sidewalls of the ruthenium liner, and is out of physical contact with the metallization layer,
• wherein a portion of the film is disposed on top of and covers part of an upper portion of the ruthenium liner, and
• wherein a lower portion of the ruthenium liner is under the upper portion of the ruthenium liner and is in physical contact with the metallization layer.