Dummy vias for damascene process
View Patent ↗An integrated circuit device and method of making the integrated circuit device are disclosed. An exemplary apparatus includes: a semiconductor layer; and a dielectric layer on the semiconductor layer, the dielectric layer having conductive vias and dummy vias formed therein, wherein the conductive vias and dummy vias extend varying distances into the dielectric layer, the conductive vias extending through the dielectric layer to the semiconductor layer, and the dummy vias extending through the dielectric layer to a distance above the semiconductor layer.
1. A semiconductor device, comprising:
a first plurality of conductive lines formed in a low-k dielectric layer on a substrate;
a second plurality of conductive lines formed in the low-k dielectric layer and disposed over the first plurality of conductive lines;
a first plurality of conductive vias disposed between the first and second plurality of conductive lines, each of the first plurality of conductive vias being connected to one of the first plurality of conductive lines and one of the second plurality of conductive lines; and
a second plurality of conductive vias disposed between and isolated from the first and second plurality of conductive lines, wherein top surfaces of the second plurality of conductive lines and top surfaces of the second plurality of conductive vias are substantially coplanar.
2. The semiconductor device of claim 1 wherein the second plurality of conductive vias have shapes selected from the group consisting of a square, a rectangle, a rectangular array, a broken stripe, a dotted stripe, a circle, a triangle, polygon, and a cross.
3. The semiconductor device of claim 1 wherein the second plurality of conductive vias have via size not less than about 0.8*minimum via size of the first plurality of conductive vias.
4. The semiconductor device of claim 1 wherein the second plurality of conductive vias are positioned such that a leveling effect is minimized.
5. The semiconductor device of claim 1 wherein the second plurality of conductive vias are positioned such that the total density of the first and second plurality of conductive vias are uniformly distributed.
6. The semiconductor device of claim 1 wherein the second plurality of conductive vias comprise a material selected from the group consisting of copper, tungsten, titanium, titanium nitride, tantalum, tantalum nitride, and combinations thereof.
7. The semiconductor device of claim 1 further comprising an etch-stop layer disposed at an interface between the first plurality of conductive lines and the first plurality of conductive vias.
8. The semiconductor device of claim 1 wherein the second plurality of conductive vias are disposed a distance above the first plurality of conductive lines.
9. The semiconductor device of claim 1 wherein a third plurality of conductive vias are disposed between the first plurality of conductive lines and active regions of the substrate.
10. The semiconductor device of claim 9 wherein the third plurality of conductive vias are positioned such that the first plurality of conductive lines and active regions of the substrate are electrically coupled.
11. The semiconductor device of claim 9 wherein the active regions of the substrate comprise at least one of a source, a drain, or a gate.
12. An apparatus comprising:
a semiconductor layer;
a dielectric layer on the semiconductor layer, the dielectric layer having conductive vias and dummy vias formed therein, wherein the conductive vias and dummy vias extend varying distances into the dielectric layer, the conductive vias extending through the dielectric layer to the semiconductor layer, and the dummy vias extending through the dielectric layer to a distance above the semiconductor layer.
13. The apparatus of claim 12 wherein the dielectric layer is a low-k dielectric layer.
14. The apparatus of claim 12 wherein the dielectric layer further has trenches, wherein the conductive vias extend from at least one of the trenches through the dielectric layer to the semiconductor layer.
15. The apparatus of claim 12 wherein the semiconductor layer includes active regions, wherein each of the conductive vias extending through the dielectric layer to the semiconductor layer are coupled to at least one of the active regions.
16. The apparatus of claim 12 wherein the dummy vias extending through the dielectric layer to the distance above the semiconductor layer are isolated from the conductive vias.
17. The apparatus of claim 12 wherein the dummy vias comprise a material selected from the group consisting of copper, tungsten, titanium, titanium nitride, tantalum, tantalum nitride, and combinations thereof.
18. The apparatus of claim 12 wherein the dummy vias are positioned such that a leveling effect is minimized.
19. An apparatus comprising:
a substrate;
a first conductive line formed in a low-k dielectric layer on the substrate;
a second conductive line formed in the low-k dielectric layer and disposed over the first conductive line;
a first conductive via disposed between and coupled to the first and second conductive lines; and
a second conductive via disposed between and isolated from the first and second conductive lines, wherein a top surface of the second conductive line and a top surface of the second conductive via are substantially coplanar.
20. The apparatus of claim 19 further comprising a third conductive via disposed between the first conductive line and the substrate, wherein the third conductive via is coupled to the first conductive line and an active region in the substrate.