Semiconductor structure and method of manufacturing the same

A method of manufacturing a semiconductor structure, comprising:

• forming a dielectric layer over a conductive layer, wherein the dielectric layer has an opening exposing a portion of the conductive layer;
• filling a ruthenium-containing material in the opening and in contact with the dielectric layer;
• and
• polishing the ruthenium-containing material using a slurry comprising an oxidizer to oxidize ruthenium of the ruthenium-containing material to form ruthenium oxide in the opening and laterally between the dielectric layer and the ruthenium-containing material.

A method, comprising:

• forming a dielectric layer over a conductive layer;
• etching the dielectric layer to form an opening extending through the dielectric layer;
• overfilling the opening in the dielectric layer with a ruthenium material;
• and
• performing a chemical mechanical polishing (CMP) process on the ruthenium material at least until the dielectric layer is exposed, wherein the CMP process produces by-products in an interspace between the ruthenium material and a sidewall of the opening to block a slurry used in the CMP process from penetrating through the interspace between the ruthenium material and the sidewall of the opening.