Methods of forming microelectronic devices, and related microelectronic devices, memory devices, and electronic systems

A microelectronic device includes a first conductive structure, a barrier structure, a conductive liner structure, and a second conductive structure. The first conductive structure is within a first filled opening in a first dielectric structure. The barrier structure is within the first filled opening in the first dielectric structure and vertically overlies the first conductive structure. The conductive liner structure is on the barrier structure and is within a second filled opening in a second dielectric structure vertically overlying the first dielectric structure. The second conductive structure vertically overlies and is horizontally surrounded by the conductive liner structure within the second filled opening in the second dielectric structure. Memory devices, electronic systems, and methods of forming microelectronic devices are also described.