In this work the nucleation and growth of CVD Cu on MOCVD TIN barrier layer as well as on PVD Ta with and without a PVD Cu seed layer on top were studied. Scanning and transmission electron microscopy was used to characterize the dependence of morphology and microstructure on deposition time. XRD measurements were carried out to study the orientation of the polycrystalline films. Atomic force microscopy was applied to investigate the surface topography. A random crystal orientation and an amorphous interlayer between the CVD Cu film and the barrier - leading to a poor adhesion performance of the CVD Cu films - were obtained on Ta and TiN, where island growth can be observed. A CVD Cu film deposited on top of PVD Cu leads to a highly preferred 〈111〉 orientation and a significantly improved adhesion of the Cu film. A PVD Cu seed layer as thin as 60 A was found to produce an epitaxially grown 〈111〉 textured Cu film. These results highlight the importance of the initial growth stages for both morphology and adhesion of the CVD Cu films.
|Number of pages
|Materials Research Society Symposium - Proceedings
|Published - 1999
|Proceedings of the 1999 MRS Spring Meeting - Symposium N: 'Advanced Interconnects and Contacts' - San Francisco, CA, United States
Duration: 5 Apr 1999 → 7 Apr 1999