Copper interconnection structures and semiconductor devices
View Patent ↗A copper interconnection structure includes an insulating layer, an interconnection body including copper in an opening provided on the insulating layer and a barrier layer including a metal element and copper, formed between the insulating layer and the interconnection body. An atomic concentration of the metal element in the barrier layer is accumulated toward an outer surface of the barrier layer facing the insulating layer, and an atomic concentration of copper in the barrier layer is accumulated toward an inner surface of the barrier layer facing the interconnection body. The inner surface of the barrier layer comprises copper surface orientation of {111} and {200}, and an intensity of X-ray diffraction peak from the inner surface of the barrier layer is stronger for the {111} peak than for the {200} peak.
1. A copper interconnection structure comprising:
an insulating layer;
an interconnection body including copper in an opening provided on the insulating layer; and
a barrier layer, comprising a metal element and copper, formed between the insulating layer and the interconnection body, and wherein:
an atomic concentration of the metal element in the barrier layer is accumulated toward an outer surface of the barrier layer facing the insulating layer, and an atomic concentration of copper in the barrier layer is accumulated toward an inner surface of the barrier layer facing the interconnection body, and
the inner surface of the barrier layer comprises copper surface orientation of {111} and {200}, and an intensity of X-ray diffraction peak from the inner surface of the barrier layer is stronger for the {111} peak than for the {200} peak;
wherein the barrier layer comprises a first barrier layer and a second barrier layer,
wherein the first barrier layer has a multilayer structure which comprises:
a first layer comprising tantalum nitride formed on the insulating layer, and
a second layer comprising tantalum formed over the first layer.
2. The copper interconnection structure of claim 1 , wherein the barrier layer further comprises an atomic concentration of oxygen accumulated toward the outer surface of the barrier layer showing similar distribution as the atomic concentration of the metal element.
3. The copper interconnection structure of claim 1 , wherein an enthalpy of oxide formation for the metal element is lower than the enthalpy of oxide formation for copper.
4. The copper interconnection structure of claim 3 , wherein the metal element has a diffusion coefficient greater than a self diffusion coefficient of copper.
5. The copper interconnection structure of claim 1 , wherein the metal element comprises at least one or more of magnesium (Mg), manganese (Mn), and aluminum (Al).
6. The copper interconnection structure of claim 1 , wherein the intensity of X-ray diffraction peak from the inner surface of the barrier layer is about 10 times stronger for the {111} peak than for the {200} peak.
7. A semiconductor device comprising circuits which are interconnected with a copper interconnection structure as a circuit interconnection, wherein said copper interconnection structure is the copper interconnection structure of claim 1 .
8. A copper interconnection structure comprising:
an insulating layer including silicon;
an interconnection body including copper in an opening provided on the insulating layer; and
a barrier layer formed between the insulating layer and the interconnection body, wherein the barrier layer comprises:
a first barrier layer comprising a first metal element having an enthalpy of oxide formation lower than the enthalpy of oxide formation for silicon, wherein the first barrier layer is formed on an inner surface of the opening, and
a second barrier layer, comprising a second metal element and copper, formed on the first barrier layer, and wherein:
an atomic concentration of the second metal element in the second barrier layer is accumulated toward an outer surface of the second barrier layer facing the first barrier layer, and an atomic concentration of copper in the second barrier layer is accumulated toward an inner surface of the second barrier layer facing the interconnection body, and
the inner surface of the second barrier layer comprises copper surface orientation of {111} and {200}, and an intensity of X-ray diffraction peak from the inner surface of the barrier layer is stronger for the {111} peak than for the {200} peak
wherein the first barrier layer has a multilayer structure which comprises:
a first layer comprising tantalum nitride formed on the insulating layer, and
a second layer comprising tantalum formed over the first layer.
9. The copper interconnection structure of claim 8 , wherein the second barrier layer further comprises an atomic concentration of oxygen accumulated toward the outer surface of the second barrier layer showing similar distribution as the atomic concentration of the second metal element.
10. The copper interconnection structure of claim 8 , wherein the first metal element comprises tantalum and at least one of scandium (Sc), titanium (Ti), vanadium (V), chrome (Cr), yttrium (Y), zirconium (Zr), niobium (Nb), antimony (Sb), hafnium (Hf), and rhenium (Re).
11. The copper interconnection structure of claim 10 , wherein the first metal element comprises tantalum and titanium.
12. The copper interconnection structure of claim 8 , wherein an enthalpy of oxide formation for the second metal element is lower than the enthalpy of oxide formation for copper.
13. The copper interconnection structure of claim 12 , wherein the second metal element has a diffusion coefficient greater than a self diffusion coefficient of copper.
14. The copper interconnection structure of claim 8 , wherein the second metal element comprises at least one or more of magnesium (Mg), manganese (Mn), and aluminum (Al).
15. The copper interconnection structure of claim 8 , wherein the intensity of X-ray diffraction peak from the inner surface of the second barrier layer is about 10 times stronger for the {111} peak than for the {200} peak.
16. The copper interconnection structure of claim 8 , wherein a total thickness of said first and second barrier layers is set to be not more than 12% of an interconnection width.
17. A semiconductor device comprising circuits which are interconnected with a copper interconnection structure as a circuit interconnection, wherein said copper interconnection structure is the copper interconnection structure of claim 8 .
18. A copper interconnection structure comprising:
an insulating layer including silicon;
an interconnection body including copper, having an interconnection width in an opening provided on the insulating layer; and
a barrier layer formed between the insulating layer and the interconnection body, wherein the barrier layer comprises:
a first barrier layer comprising a first metal element having an enthalpy of oxide formation lower than the enthalpy of oxide formation for silicon, wherein the first barrier layer is formed on an inner surface of the opening, and
a second barrier layer, comprising a second metal element and copper, formed on the first barrier layer, and wherein:
an atomic concentration of the second metal element in the second barrier layer is accumulated toward an outer surface of the second barrier layer facing the first barrier layer, and an atomic concentration of copper in the second barrier layer is accumulated toward an inner surface of the second barrier layer facing the interconnection body, and
a total thickness of said first and second barrier layers is set to be not more than 12% of the interconnection width,
wherein the second metal element comprises germanium.
19. The copper interconnection structure of claim 18 , wherein the inner surface of the second barrier layer comprises copper surface orientation of {111} and {200}.
20. The copper interconnection structure of claim 19 , wherein an intensity of X-ray diffraction peak from the inner surface of the barrier layer is stronger for the {111} peak than for the {200} peak.
21. The copper interconnection structure of claim 20 , wherein the intensity of X-ray diffraction peak from the inner surface of the barrier layer is about 10 times stronger for the {111} peak than for the {200} peak.
22. The copper interconnection structure of claim 18 , wherein the second metal element further comprises at least one of magnesium (Mg), manganese (Mn), and aluminum (Al).
23. The copper interconnection structure of claim 18 , wherein the inner surface of the barrier layer comprises copper surface orientation of {111}.
24. The copper interconnection structure of claim 18 , wherein the second barrier layer further comprises an atomic concentration of oxygen accumulated toward the outer surface of the second barrier layer showing similar distribution as the atomic concentration of the second metal element.
25. The copper interconnection structure of claim 18 , wherein an enthalpy of oxide formation for the second metal element is lower than the enthalpy of oxide formation for copper.
26. The copper interconnection structure of claim 25 , wherein the second metal element has a diffusion coefficient greater than a self diffusion coefficient of copper.