Semiconductor devices with enhanced electromigration performance

1. A structure comprising:

a last metal line in electrical contact with an underlying device; and

at least one staple structure in direct electrical contact with the last metal line, the at least one staple structure reducing electromigration issues in the last metal line, wherein

the at least one staple structure is formed in a dielectric material, a plurality of vias and a trench spanning between the plurality of vias, and

the plurality of vias and the trench are lined with a conductive liner and the plurality of vias and the trench are filled with a conductive material to form a conductive bar in direct electrical contact with the conductive liner in the vias.

2. The structure of claim 1 , wherein the at least one staple structure is structured such that electrical current passing through the last metal line and also passes through the at least staple structure to reduce electromigration issues.

3. The structure of claim 1 , wherein the plurality of vias is two vias in direct electrical contact with the last metal line and which are spaced apart less than a Blech length.

4. The structure of claim 1 , wherein the at least one staple structure comprises:

a plurality of staggered staple structures in the dielectric material, in direct electrical contact with the at last metal line.

5. The structure of claim 1 , wherein the last metal line is in electrical contact with a bipolar transistor and the at least one staple structure provides a blocking zone.

6. A structure comprising:

a last metal line in electrical contact with an underlying device; and

at least one staple structure in direct electrical contact with the last metal line, the at least one staple structure reducing electromigration issues in the last metal line, wherein

the at least one staple structure is formed in a dielectric material, a plurality of vias and a trench spanning between the plurality of vias, and

the plurality of vias and the trench are lined with tantalum, nitride or ruthenium, and then filled with copper material to form the at least one staple structure.

7. The structure of claim 6 , further comprising a cap layer of SiN over the trench.

8. A structure comprising:

a last metal line in electrical contact with an underlying device; and

at least one staple structure in direct electrical contact with the last metal line, the at least one staple structure reducing electromigration issues in the last metal line, wherein the at least one staple structure comprises:

a plurality of vias in the dielectric material, a plurality of trenches in the dielectric material, each of which are in contact with at least two of the plurality of vias;

the plurality of vias and trenches are lined with a conductive liner;

the plurality of vias and trenches are filled with a conductive material over the conductive liner; and

the trenches are capped with a capping material.

9. The structure of claim 8 , wherein:

the conductive liner is tantalum, nitride or ruthenium;

the conductive material is copper; and

the capping material is SiN.