Patent ID: 7851360

Claim:
A method comprising: forming a first layer comprising a material selected from the group consisting of a metal nitride, a metal carbide and a metal carbonitride on a substrate wherein the substrate includes at least one trench etched into a dielectric layer of the substrate; forming a second layer on the first layer, the second layer comprising a material selected from the group consisting of ruthenium, tantalum and a combination thereof wherein (i) if a ruthenium layer is formed, forming comprises introducing a ruthenium-containing precursor selected from the group consisting of RuRR′R″, (Ring)RuL 2 R, (Ring)RuLL′R and (Ring)Ru[(η 3 -R)(Ring)RuL 2 ] where R is a negatively charged two-electron donor; L is a neutral two-electron donor; η 3 -R is a negatively charged chelating four-electron donor; and Ring is an unfunctionalized or functionalized member of a group comprising cyclic dienes, pyrroles, dienes, boratabenzene and dienes containing heteroatoms; or (ii) if a tantalum layer is formed, forming comprises introducing a tantalum-containing precursor selected from the group consisting of allylTa(CH 3 ) 3 where allyl is η 3 C 3 H 5 ; (C 5 H 5 ) 2 TaR variations where R is amide or alkyl substituents; Ta(borilidiene)-containing precursors; (PR 3 ═N)Ta variations where R is a hydrogen, an alkyl or a phenyl substituent and PR 3 =N is a phosphinamide ligand; and selenium analogs thereof where R is a ring structure selected from the group consisting of cyclic dienes, mesityl, phenyl, tolyl, pyrroles and pyridyl; and depositing a third layer comprising copper on the second layer and within the at least one trench.