Electronic fuse vias in interconnect structures
View Patent ↗An electronic fuse and method for forming the same. Embodiments of the invention include e-fuses having a first metallization level including a metal structure, a second metallization level above the first metallization level, a metal via in the second metallization level, an interface region where the metal via meets the first metallization level, and a damaged region at the interface region. Embodiments further include a method including providing a first metallization level including a metal structure, forming a capping layer on the first metallization level, forming an opening in the capping layer that exposes a portion of the metal structure; forming above the capping layer an adhesion layer contacting the metal structure, forming an insulating layer above the adhesion layer, etching the insulating layer and the adhesion layer to form a recess exposing the metal structure, and filling the fuse via recess to form a fuse via.
1. A vertical electronic fuse structure, the structure comprising:
a first metallization level including a first metal structure;
a second metallization level above the first metallization level comprising:
a capping layer above and in direct contact with the first metallization level, the capping layer has an opening above the first metal structure;
an adhesion layer separating the second metallization level from the capping layer, at least a portion of the adhesion layer contacts an upper surface the first metal structure within the opening in the capping layer;
a metal via passing through the adhesion layer, the metal via is in direct contact with an upper surface of the first metal structure;
an e-fuse interface region where the metal via meets the first metallization level; and
a damaged region at the e-fuse interface region.
2. The structure of claim 1 , wherein the damaged region comprises a flared bottom portion of the metal via.
3. The structure of claim 1 , wherein the damaged region comprises a void.
4. The structure of claim 1 , wherein the damaged region comprises an undercut in at least one of the capping layer and the adhesion layer.
5. The structure of claim 1 , wherein the first metal structure comprises a weakened region comprising oxygen in direct contact with the metal via.
6. The structure of claim 1 , wherein the capping layer comprises a nitrogen containing film and wherein the adhesion layer includes silicon and oxygen.
7. The structure of claim 1 , wherein the second metallization level further comprising:
an insulator layer above and in direct contact with the adhesion layer, the insulator layer fills the opening of the capping layer and the metal via passes through the insulator layer.
8. A vertical electronic fuse structure, the structure comprising:
a first metallization level including a first metal structure;
a second metallization level above the first metallization level comprising:
a capping layer above and in direct contact with the first metallization level, the capping layer has an opening above the first metal structure;
an adhesion layer above and in direct contact with the capping layer, the adhesion layer lines at least a portion of the opening in the capping layer; and
an insulator layer above and in direct contact with the adhesion layer, wherein the insulator layer fills the opening of the capping layer;
a metal via passing through the insulator layer and the adhesion layer, the metal via is in direct contact with an upper surface of the first metal structure; and
a damaged region at the e-fuse interface region where the metal via meets the first metallization level.
9. The structure of claim 8 , wherein the damaged region comprises a flared bottom portion of the metal via.
10. The structure of claim 8 , wherein the damaged region comprises a void.
11. The structure of claim 8 , wherein the damaged region comprises an undercut in at least one of the capping layer, the adhesion layer, and the second insulator.
12. The structure of claim 8 , wherein the first metal structure comprises a weakened region comprising oxygen in direct contact with the metal via.
13. The structure of claim 8 , wherein the capping layer comprises a nitrogen containing film and wherein the adhesion layer includes silicon and oxygen.
14. A vertical electronic fuse structure, the structure comprising:
a first metallization level including a first metal structure adjacent to a second metal structure;
a second metallization level above the first metallization level, wherein the second metallization level includes a first metal via in direct contact with the first metal structure and a second metal via in direct contact with the second metal structure;
a capping layer above and in direct contact with an upper surface of the first metal structure and an upper surface of the second metal structure; and
an adhesion layer above and in direct contact with the capping layer, a portion of the adhesion layer is above and in direct contact with the second metal structure but not the first metal structure.
15. The structure of claim 14 , wherein the damaged region comprises a flared bottom portion of the metal via.
16. The structure of claim 14 , wherein the damaged region comprises a void.
17. The structure of claim 14 , wherein the damaged region comprises an undercut in at least one of the capping layer, the adhesion layer, and the second insulator.
18. The structure of claim 14 , wherein the capping layer comprises a nitrogen containing film and wherein the adhesion layer includes silicon and oxygen.
19. The structure of claim 14 , wherein the first metal structure comprises a weakened region comprising oxygen in direct contact with the metal via.