Abstract: An interconnect structure is provided that has improved electromigration resistance as well as methods of forming such an interconnect structure. The interconnect structure includes a composite M-MOx cap located at least on the upper surface of the Cu-containing material within the at least one opening. The composite M-MOx cap includes an upper region that is composed of the metal having a higher affinity for oxygen than copper and copper oxide and a lower region that is composed of a non-stoichiometric oxide of said metal.

Abstract: An interconnect structure is provided that has improved electromigration resistance as well as methods of forming such an interconnect structure. The interconnect structure includes an interconnect dielectric material having a dielectric constant of about 4.0 or less. The interconnect dielectric material has at least one opening therein that is filled with a Cu-containing material. The Cu-containing material within the at least one opening has an exposed upper surface that is co-planar with an upper surface of the interconnect dielectric material. The interconnect structure further includes a composite M-MOx cap located at least on the upper surface of the Cu-containing material within the at least one opening. The composite M-MOx cap includes an upper region that is composed of the metal having a higher affinity for oxygen than copper and copper oxide and a lower region that is composed of a non-stoichiometric oxide of said metal.

Abstract: A dielectric capping layer having a dielectric constant of less than 4.2 is provided that exhibits a higher mechanical and electrical stability to UV and/or E-Beam radiation as compared to conventional dielectric capping layers. Also, the dielectric capping layer maintains a consistent compressive stress upon post-deposition treatments. The dielectric capping layer includes a tri-layered dielectric material in which at least one of the layers has good oxidation resistance, is resistance to conductive metal diffusion, and exhibits high mechanical stability under at least UV curing. The low k dielectric capping layer also includes nitrogen content layers that contain electron donors and double bond electrons. The low k dielectric capping layer also exhibits a high compressive stress and high modulus and is stable under post-deposition curing treatments, which leads to less film and device cracking and improved device reliability.