Interconnect with self-forming wrap-all-around barrier layer
The present invention provides interconnects with self-forming wrap-all-around graphene barrier layer. In one aspect, a method of forming an interconnect structure is provided. The method includes: patterning at least one trench in a dielectric; forming an interconnect in the at least one trench embedded in the dielectric; and forming a wrap-all-around graphene barrier surrounding the interconnect. An interconnect structure having a wrap-all-around graphene barrier is also provided.
1. A method of forming an interconnect structure, the method comprising the steps of:
patterning at least one trench in a dielectric;
forming an interconnect in the at least one trench embedded in the dielectric; and
forming a wrap-all-around graphene barrier surrounding the interconnect, wherein the step of forming the wrap-all-around graphene barrier surrounding the interconnect further comprises the steps of:
depositing a graphene layer on top of the interconnect; and
annealing the interconnect and the graphene layer under conditions sufficient to diffuse carbon atoms from the graphene layer to form a buried graphene layer at an interface between the dielectric and the interconnect, wherein the graphene layer and the buried graphene layer form the wrap-all-around graphene barrier layer surrounding the interconnect.
2. The method of claim 1 , wherein the conditions comprise a temperature of from about 25° C. to about 260° C. and ranges therebetween, and a duration of from about 1 minute to about 30 minutes and ranges therebetween.
3. The method of claim 1 , wherein the step of forming the wrap-all-around graphene barrier surrounding the interconnect further comprises the step of:
concurrently forming a graphene layer on top of the interconnect and a buried graphene layer at an interface between the dielectric and the interconnect, wherein the graphene layer and the buried graphene layer form the wrap-all-around graphene barrier layer surrounding the interconnect.
4. The method of claim 1 , wherein the dielectric comprises a material selected from the group consisting of: silicon oxide (SiOx), organosilicate glass (SiCOH), porous organosilicate glass (pSiCOH), and combinations thereof.
5. The method of claim 1 , wherein the step of forming the interconnect in the at least one trench comprises the step of:
depositing a metal into and filling the at least one trench, wherein the metal is selected from the group consisting of: cobalt (Co), ruthenium (Ru) and combinations thereof.
6. The method of claim 1 , wherein the graphene layer and the buried graphene layer each comprises from about 1 monolayer to about 5 monolayers of graphene.
7. A method of forming an interconnect structure, the method comprising the steps of:
patterning at least one trench in a dielectric;
depositing a metal liner into and lining the at least one trench;
depositing a conformal carbon layer onto the metal liner;
depositing a fill metal into the at least one trench over the metal liner, wherein the metal liner and the fill metal form an interconnect in the at least one trench embedded in the dielectric;
depositing a second dielectric over the interconnect; and
annealing the interconnect and the conformal carbon layer under conditions sufficient to diffuse carbon atoms from the conformal carbon layer to form graphene layers at an interface between the dielectric and the interconnect, and at an interface between the second dielectric and the interconnect, wherein the graphene layers form a wrap-all-around graphene barrier layer surrounding the interconnect.
8. The method of claim 7 , wherein the metal liner comprises a metal selected from the group consisting of: Co, Ru and combinations thereof.
9. The method of claim 7 , wherein the fill metal comprises a same metal as the metal liner.