Methods of forming interconnect structure

An interconnect structure, along with methods of forming such, are described. In some embodiments, the method includes forming a first dielectric layer over one or more devices, forming a first conductive feature in the first dielectric layer, and forming two dielectric features over the first dielectric layer and the first conductive feature. At least one of the two dielectric features has a first width, and each dielectric feature includes a first low-k dielectric layer, an oxide layer, and a first etch stop layer. The method further includes forming a second conductive feature between the two dielectric features, and the second conductive feature has a second width substantially the same as the first width.