Interconnect structure for semiconductor devices
A method of manufacturing a semiconductor device with a cap layer for a copper interconnect structure formed in a dielectric layer is provided. In an embodiment, a conductive material is embedded within a dielectric layer, the conductive material comprising a first material and having either a recess, a convex surface, or is planar. The conductive material is silicided to form an alloy layer. The alloy layer comprises the first material and a second material of germanium, arsenic, tungsten, or gallium.
1. A semiconductor device comprising:
a first dielectric layer;
a trench in the first dielectric layer;
a conductive material at least partially filling the trench, the conductive material comprising copper; and
a cap layer on the conductive material, the cap layer comprising copper-metal silicide, wherein a metal of the copper-metal silicide comprises germanium.
2. The semiconductor device of claim 1 , further comprising a second dielectric layer formed in physical contact over the cap layer and the first dielectric layer.
3. The semiconductor device of claim 1 , further comprising an etch stop layer formed over the cap layer and the first dielectric layer, and a second dielectric layer formed over the etch stop layer.
4. The semiconductor device of claim 1 , wherein the first dielectric layer comprises a low-K dielectric.
5. The semiconductor device of claim 1 , further comprising a barrier layer interposed between the conductive material and sidewalls of the trench.
6. The semiconductor device of claim 5 , wherein the barrier layer comprises titanium, titanium nitride, tantalum, or tantalum nitride.
7. The semiconductor device of claim 5 , wherein the barrier layer is conductive.
8. A semiconductor device comprising:
a copper interconnect in a first dielectric layer; and
a copper-metal silicide layer on the copper interconnect, wherein the copper-metal silicide layer comprises arsenic.
9. The semiconductor device of claim 8 , further comprising a second dielectric layer formed directly over the copper-metal silicide layer and the first dielectric layer.
10. The semiconductor device of claim 8 , further comprising an etch stop layer formed over the copper-metal silicide layer and the first dielectric layer, and a second dielectric layer formed over the etch stop layer.
11. The semiconductor device of claim 8 , wherein the first dielectric layer comprises a low-K dielectric.
12. The semiconductor device of claim 8 , further comprising a barrier layer interposed between a conductive material of the copper interconnect and sidewalls of a trench.
13. The semiconductor device of claim 12 , wherein the barrier layer comprises titanium, titanium nitride, tantalum, or tantalum nitride.
14. A semiconductor device comprising:
a first dielectric layer;
a copper interconnect formed in the first dielectric layer;
a copper alloy silicide layer on the copper interconnect; and
a second dielectric layer over the first dielectric layer and the copper alloy silicide layer, wherein the copper alloy silicide layer comprises tungsten.
15. The semiconductor device of claim 14 , further comprising an etch stop layer formed between the copper alloy silicide layer and the second dielectric layer.
16. The semiconductor device of claim 14 , wherein the first dielectric layer comprises a low-K dielectric.
17. The semiconductor device of claim 14 , further comprising a conductive barrier layer interposed between copper of the copper interconnect and sidewalls of a trench.
18. A semiconductor device comprising:
a first dielectric layer;
a trench in the first dielectric layer;
a conductive material at least partially filling the trench, the conductive material comprising copper; and
a cap layer on the conductive material, the cap layer comprising copper-metal silicide, wherein a metal of the copper-metal silicide comprises gallium.
19. The semiconductor device of claim 18 , further comprising a conductive barrier layer interposed between the conductive material and the first dielectric layer.
20. The semiconductor device of claim 19 , wherein the conductive barrier layer comprises titanium, titanium nitride, tantalum, or tantalum nitride.