A semiconductor device includes a substrate, at least one layer of
functional devices formed on the substrate, a first dielectric layer
formed over the functional device layer and a first trench/via located in
the first dielectric layer. A copper conductor fills the first
trench/via. An electromigration inhibiting barrier layer is selectively
located over a surface of the copper conductor and not any other
remaining exposed surface. An insulating cap layer overlies the barrier
layer and the remaining exposed surface. A second dielectric layer
overlies the insulating cap layer. A second trench/via is located in the
second dielectric layer and extends through the insulating cap layer and
the barrier layer. A micro-trench is located within the first dielectric
layer and is associated with the formation of the second trench/via. The
micro-trench exposes a portion of the copper conductor. A filler fills
the micro-trench. The filler is formed from a material used to form the
electromigration inhibiting barrier layer.