Semiconductor structure and method for manufacturing the same
A semiconductor structure includes an integrated circuit, a first dielectric layer over the integrated circuit, an etch stop layer over the first dielectric layer, a barrier layer over the etch stop layer, a conductive layer over the barrier layer, and a void region vertically extending through the conductive layer, the barrier layer, and the etch stop layer. The void region has an upper portion, a middle portion below the upper portion, and a lower portion below the middle portion, the middle portion. The middle portion is narrower than the upper portion and the lower portion.
1. A semiconductor structure, comprising:
an integrated circuit;
a low-k dielectric layer over the integrated circuit;
an etch stop layer over the low-k dielectric layer, wherein a portion of the etch stop layer has a straight sidewall and a concave sidewall;
a barrier layer over the etch stop layer and in contact with the low-k dielectric layer, wherein the barrier layer is in contact with a top surface of the portion of the etch stop layer and the straight sidewall of the portion of the etch stop layer;
a conductive layer over the etch stop layer; and
a void region vertically extending through the conductive layer, the barrier layer, and the etch stop layer, wherein the concave sidewall of the portion of the etch stop layer is exposed to the void region.
2. The semiconductor structure of claim 1 , wherein a first end of the barrier layer is exposed to the void region.
3. The semiconductor structure of claim 2 , further comprising a dielectric layer over the conductive layer, wherein a second end of the barrier layer is in contact with the dielectric layer.
4. The semiconductor structure of claim 1 , further comprising:
a capping layer covering the conductive layer; and
a dielectric layer over the capping layer.
5. The semiconductor structure of claim 4 , wherein a first end of the capping layer is exposed to the void region.
6. The semiconductor structure of claim 5 , wherein a second end of the capping layer is covered by the dielectric layer.
7. The semiconductor structure of claim 5 , wherein the first end of the capping layer is separated from the concave sidewall of the portion of the etch stop layer by the barrier layer.
8. The semiconductor structure of claim 1 , wherein the void region has an upper portion, a middle portion below the upper portion, and a lower portion below the middle portion, the middle portion, wherein the middle portion is narrower than the upper portion and the lower portion.
9. A semiconductor structure, comprising:
an integrated circuit;
a first dielectric layer over the integrated circuit;
an etch stop layer over the first dielectric layer;
a barrier layer over the etch stop layer;
a conductive layer over the barrier layer; and
a void region vertically extending through the conductive layer, the barrier layer, and the etch stop layer, the void region having an upper portion, a middle portion below the upper portion, and a lower portion below the middle portion, the middle portion, wherein the middle portion is narrower than the upper portion and the lower portion, and wherein the barrier layer and the etch stop layer are exposed to the void region.
10. The semiconductor structure of claim 9 , further comprising a capping layer covering the conductive layer, wherein the conductive layer is separated from the void region by the capping layer.
11. The semiconductor structure of claim 10 , wherein the capping layer terminates prior to reaching the etch stop layer.
12. The semiconductor structure of claim 9 , wherein the lower portion of the void region has curved sidewalls.
13. The semiconductor structure of claim 12 , wherein a width of the upper portion of the void region increases as a distance from the integrated circuit increases.
14. The semiconductor structure of claim 9 , wherein a topmost position of the void region is higher than a top surface of the conductive layer.
15. A semiconductor structure, comprising:
an integrated circuit;
a first dielectric layer over the integrated circuit;
an etch stop layer over the first dielectric layer;
a conductive layer over the barrier layer, wherein the conductive layer has a via portion extends downwardly through the etch stop layer and the first dielectric layer, and the etch stop layer has a first portion and a second portion respectively on opposite sides of the via portion of the conductive layer;
a void region vertically extending through the conductive layer, the barrier layer and the etch stop layer, wherein the first portion of the etch stop layer is exposed to the void region; and
a second dielectric layer covering the conductive layer, wherein the second portion of the etch stop layer is in contact with the second dielectric layer, and wherein the second portion of the etch stop layer forms a curved interface with the second dielectric layer.
16. The semiconductor structure of claim 15 , wherein the first portion of the etch stop layer is exposed to the void region and is separated from the second dielectric layer.
17. The semiconductor structure of claim 15 , further comprising a barrier layer extending from a sidewall of the second portion of the etch stop layer to a top surface of the second portion of the etch stop layer.
18. The semiconductor structure of claim 17 , wherein the barrier layer is in contact with the second dielectric layer.
19. The semiconductor structure of claim 15 , wherein the void region has an upper portion, a middle portion below the upper portion, and a lower portion below the middle portion, the middle portion, wherein the middle portion is narrower than the upper portion and the lower portion.
20. The semiconductor structure of claim 19 , wherein the lower portion of the void region has curved sidewalls.