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

Paper TF-TuA10
Surface Structural Anisotropy in Sputter and Electrolytic Deposited Tantalum Films

Tuesday, October 30, 2001, 5:00 pm, Room 123

Session: Growth and Properties of Thin Films
Presenter: S.L. Lee, US Army Armament Research Development and Engineering Center
Authors: S.L. Lee, US Army Armament Research Development and Engineering Center
D. Windover, Rensselaer Polytechnic Institute
Correspondent: Click to Email
We studied the growth surface texture of tantalum films generated by sputter and electrolytic deposition processes for high temperature and pressure wear and erosion applications, using conventional and image plate XRD. Electrochemically deposited bcc tantalum coating in eutectic molten salt solution at 800°C on 20mm-diameter 4340 steel cylinder revealed near random grain orientation. Triode sputtered tantalum deposition on steel generally showed weak anisotropy. Example specimens deposited in krypton gas at 200°C-250°C revealed (110) and (211) texture with poles. Planar magnetron sputtered tantalum film on a steel plate with a thin electrolytic chromium interface layer produced bcc tantalum film with (111) fiber texture, following the (111) fiber texture in chromium. Planar magnetron sputter-deposited 200nm film on a (100) silicon wafer, mixed bcc and tetragonal tantalum and (110) fiber texture with azimuth symmetry evolved. Random oriented grain distribution suggests uniform thermal-mechanical properties in polycrystalline solids. Model calculations of Young’s modulus and Poisson’s ratio for isotropic tantalum crystalline aggregates were made. Evaluation of directional modulus, e.g., E110, E100, E111, from single crystal elastic constants, suggested higher elastic modulus in the out-of-plane direction for (111) fiber-textured films.