Mr. Shaul Pagis-Sharon - M.Sc. Candidate
15/02/2026
David Wang Auditorium, 3rd Floor, Dalia Maydan Bldg.
11:30
Sputter deposition is a common physical deposition method for creating metallic and functional thin films. Controlling material properties during deposition is critical for informed processing and subsequent application. One of the ways to do that is to introduce porosity in the substrate, which can also reduce the interface adhesive forces and increase the piezoelectric coefficient of piezoelectric substrates. A quantitative model was developed for the columnar growth of material in low-temperature sputter deposition on a porous substrate, expanding an earlier phenomenological model assuming the crystallites are shaped as parabolic cones, i.e. h~r2. The work provides a theoretical justification for this shape and introduces the substrate porosity as a model parameter. Simulations using the model predict a positive correlation between the substrate porosity, ranging 0-60% and the sputtered layer porosity, final film thickness and roughness. The model predicted an enhancement in film thickness, e.g. from ~120nm on a non-porous substrate, to ~140nm on a 50% porous substrate. The simulated results were found to be in good agreement with experimental observations of sputtered iron-gallium (Galfenol) layers on porous silicon, in terms of thickness, porosity and roughness. This model provides a practical tool for understanding, controlling and designing sputtered thin films on porous substrates.