Development of a piezoelectric lead titanate thin film process on silicon substrates by high rate gas flow sputtering

Polycrystalline lead titanate (PT) thin films in the range of 3–6 μm were crack and void free deposited on silicon substrates in a high rate gas flow sputtering process. Gas flow sputtering uses the hollow cathode effect which results into high deposition rates of about 120 nm/min. (1 1 1) Textured platinum was used as bottom electrode to assist the nucleation of PT.Material properties of the PT thin films as well as the Pt bottom electrode like topography, morphology, chemical composition, and structure are evaluated. The sputtered PT layers show clearly Perovskite traces in XRD patterns, even the (1 1 1) texture of the Pt is partial transferred. The most difficult part is to fulfil the empirical formula PbTiO₃. This problem is solved by stabilising the process parameters. It was shown that the temperature has got enormous influence at the stoichiometry.