Method of fabricating semiconductor device
View Patent ↗The present invention provides a Cu line and method of forming the same, by which reliability (e.g., EM, BTS and the like) can be enhanced by replacing SiN by HfO x , which plays a role as a protective layer and/or an etch stop layer on a Cu line, prevents or inhibits galvanic corrosion due to Cu oxide, and inhibits or reduces additional formation of Cu oxide by gathering or scavenging oxygen atoms from —OH, O 2 , and H 2 O. The present method includes the steps of forming a trench in an insulating layer on a substrate, forming a planarized Cu layer in the trench, forming a HfO x layer on the planarized Cu layer, and thermally treating the substrate.
1. A method of fabricating a semiconductor device, comprising the steps of:
forming a trench pattern in an insulating layer on a substrate;
forming a planarized Cu layer in the trench pattern;
depositing a protective layer comprising HfO 2 on the planarized Cu layer;
depositing a barrier layer on the protective layer; and thermally treating the substrate.
2. The method of claim 1 , wherein the barrier layer comprises silicon nitride.
3. The method of claim 1 , wherein forming the trench pattern comprises a damascene process.
4. A method of fabricating a semiconductor device, comprising the steps of:
forming a trench pattern in an insulating layer on a substrate;
forming a planarized Cu layer in the trench pattern;
depositing a protective layer comprising HfO 2 on the planarized Cu layer, and
annealing the substrate at a temperature of from about 200 to about 700° C.
5. The method of claim 4 , wherein the annealing is conducted in an atmosphere comprising oxygen, nitrogen and/or an inert noble gas.
6. The method of claim 5 , wherein the annealing comprises an atmosphere comprising oxygen.
7. The method of claim 4 , further comprising depositing a barrier layer on the protective layer.
8. The method of claim 7 , wherein the barrier layer comprises silicon nitride.
9. A method of fabricating a semiconductor device, comprising the steps of:
forming a trench pattern in an insulating layer on a substrate;
forming a planarized Cu layer in the trench pattern;
depositing a protective layer comprising HfO 2 on the planarized Cu layer by chemical vapor deposition; and
thermally treating the substrate.
10. The method of claim 9 , wherein the deposited HfO 2 has a thickness of from about 50 to about 2,000 Å.
11. The method of claim 3 , further comprising depositing a barrier layer on the protective layer.
12. The method of claim 9 , wherein the chemical vapor deposition comprises depositing the HfO 2 from a precursor selected from the group consisting of HfCl 4 , tetra(C 1 –C 4 -alkoxy)hafnium, and tetrakis(di-C 1 –C 4 -alkylamido)hafnium.
13. The method of claim 3 , wherein forming the trench pattern comprises depositing Cu in the trench and planarizing the deposited Cu.
14. The method of claim 12 , wherein the chemical vapor deposition comprises depositing the HfO 2 from a precursor selected from the group consisting of HfCl 4 and tetrakis(di-C 1 –C 4 -alkylamido)hafnium and an oxygen source selected from the group consisting of O 2 , O 3 , and N 2 O.
15. The method of claim 3 , wherein the chemical vapor deposition is conducted at a temperature of greater then 200° C.
16. The method of claim 9 , wherein the chemical vapor deposition is conducted at a temperature of less than 200° C., and the method further comprises annealing the protective layer at a temperature of from 200 to about 700° C.
17. The method of claim 16 , wherein the annealing is conducted in an atmosphere comprising oxygen, nitrogen and/or an inert noble gas.
18. A device, comprising:
an insulating layer on a substrate, the insulating layer having a trench therein;
a planar Cu layer in the trench;
a protective layer comprising HfO 2 on the Cu layer; and
a silicon nitride layer on the protective layer.
19. The device of claim 18 , wherein the protective layer has a thickness of from about 50 to about 2,000 Å.
20. The device of claim 18 , wherein the protective layer consists essentially of HfO 2 .