Electrochemical deposition of metal layers and structures for Si-based microsystems

This work reports the study of the electrochemical (EC deposition of Ni metallic layers and Ni/Cu multilayer structures on Si based substrates. The structural analysis of the processed samples has been performed by X-ray diffraction (XRD) and these data have been correlated with the characterisation of their surface morphology by atomic force microscope (AFM) measurements. The results obtained show the strong dependence of the structural parameters of the deposited films on the substrate surface layer and growth current density, for Ni layers grown onto EC deposited Cu sacrifical ones a strong (2 2 0) preferred orientation evolves with deposition time. This is likely related to a textured structure of the Cu film. Direct deposition onto Au coated oxidised Si wafer allows to avoid this preferential orientation, but a strong decrease in the Ni growth rate is observed. Texturing of the Ni film can also be controlled by the current density during growth. (C) 2002 Elsevier Science B.V. All rights reserved.