IUVSTA 15th International Vacuum Congress (IVC-15), AVS 48th International Symposium (AVS-48), 11th International Conference on Solid Surfaces (ICSS-11)
    Thin Films Wednesday Sessions
       Session TF-WeA

Paper TF-WeA10
Sputter Deposition of Metallic Sponges

Wednesday, October 31, 2001, 5:00 pm, Room 123

Session: Nucleation and Growth
Presenter: A.F. Jankowski, Lawrence Livermore National Laboratory
Correspondent: Click to Email
The growth of thin-film metallic sponges is of interest in several electrochemical applications, for example, conductive porous electrodes for gas transport and processing.@footnote 1@ Determination of the experimental parameters needed to yield metallic sponges should be tractable for physical vapor deposition processes. The general guidelines on how to stabilize the basic coating morphologies are found in the classic zone model for film growth.@footnote 2@ It's known that morphologies in structure can range from porous columnar to dense polycrystalline as the process conditions are manipulated for either sputter deposition or evaporation. However, there's no reference to the three-dimensional structure of a sponge - that is, a polycrystal with continuous open porosity but without the definitive columnar features characteristic of vapor deposits. Herein, conditions for deposition are resolved that produce the sponge morphology augmenting the classic zone model of structure. For sputter deposition using planar magnetrons, the general conditions are an increased working gas pressure and an intermediate substrate temperature. Example results of the sponge morphology in a 1 to 2 µm thick coating are presented for metals including aluminum, gold, nickel, and silver. This work was performed under the auspices of the U.S. Department of Energy by University of California, Lawrence Livermore National Laboratory under contract No. W-7405-Eng-48. @FootnoteText@ @footnote 1@ A. Jankowski, et al., J. Vac. Sci. Technol. A, 13 (1995) 658; 18 (2000) 2003. @footnote 2@ J. Thornton, J. Vac. Sci. Technol., 14 (1974) 666.