| 摘要 |
Semiconductor devices comprising interconnects with improved adhesion of barrier layers to dielectric layers are formed by laser thermal annealing, in N2 and H2, exposed surfaces of a dielectric layer defining an opening, and then depositing Ta to form a composite layer lining the opening. Embodiments include forming a dual damascene opening in an interlayer dielectric comprising F-containing dielectric material, such as F-silicon oxide derived from F-TEOS, impinging a pulsed laser light beam on exposed surfaces of the F-silicon oxide defining the opening in a flow of N2 and H2, and then depositing Ta to form a composite barrier layer comprising graded tantalum nitride and alpha-Ta lining the opening. Laser thermal annealing in N2 and H2 depletes the exposed silicon oxide surfaces of F while enriching the surfaces with N2. Deposited Ta reacts with the N2 in the N2-enriched surface region to form a composite barrier layer comprising a graded layer of tantalum nitride and a layer of alpha-Ta thereon. Cu is then deposited, CMP conducted and a capping layer deposited to form the dual damascene structure.
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