Method of forming an interconnect structure

A method of forming an interconnect structure, the method comprising:

• depositing a lower dielectric layer over a substrate;
• forming a first recess in the lower dielectric layer;
• forming a first conductive layer in the first recess, the first conductive layer having a void;
• depositing an upper dielectric layer over the lower dielectric layer and the first conductive layer;
• forming a second recess in the upper dielectric layer, wherein the second recess exposes the first conductive layer;
• after forming the second recess, removing a portion of the first conductive layer to expose the void;
• forming a carbon-containing layer along sidewalls of the void;
• and
• forming a second conductive layer over the carbon-containing layer.

A method of forming an interconnect structure, the method comprising:

• forming a first dielectric layer;
• forming a first recess in the first dielectric layer;
• forming a first conductive layer in the first recess, an upper surface of the first conductive layer being level with an uppermost surface of the first dielectric layer, the first conductive layer having a void;
• forming a second dielectric layer over the first dielectric layer;
• after forming the second dielectric layer, forming a second recess through the second dielectric layer to the first conductive layer, wherein forming the second recess removes at least a portion of the first conductive layer to expose the void;
• forming a carbon-containing layer along sidewalls of the second recess and sidewalls of the void;
• and
• forming a second conductive layer over the carbon-containing layer, an upper surface of the second conductive layer and the second dielectric layer being level.