Interconnect structure and method of forming the same

A semiconductor device, comprising:

• a substrate including dielectric material;
• a narrow interconnect opening formed within said dielectric material;
• a wide interconnect opening formed within said dielectric material, the wide interconnect opening having a bigger feature size as compared to a feature size of the narrow interconnect opening;
• a first metal filling the narrow interconnect opening fully to form a first interconnect structure and conformally covering a surface of the wide interconnect opening formed in the dielectric material;
• and
• a second metal formed over the first metal and encapsulated by the first metal to form a second interconnect structure within the wide interconnect opening, wherein:
• the second metal has a bottom portion, a top portion, and side portions,
• the bottom portion, top portion, and side portions of the second metal are in direct contact with the first metal,
• the top portion of the second metal is covered by the first metal, and the first interconnect structure is spaced apart from the second interconnect structure by said dielectric material.