Lead-free 0.75(Bi0.5Na0.5)TiO3-0.25SrTiO3 (BNT-ST) epitaxial films grown on Si (001) substrates via pulsed laser deposition

• Epitaxial growth of LNO electrode films onto Si (001) substrates.
• Epitaxial growth of BNT-ST piezoelectric thin films on epitaxial LNO electrode films.
• High crystallinity of the BNT-ST and LNO films onto Si (001) substrates.
• No distinct diffusion of constituent elements in the BNT-ST/LNO/CeO2/YSZ structure.

Lead-free BNT-ST and La0.5Ni0.5O3 (LNO) bottom electrode films were epitaxially grown onto CeO2/YSZ (yttria stabilized zirconia) buffered Si (001) substrates via pulsed laser deposition. The lattice alignment of CeO2/YSZ and BNT-ST/LNO showed 45° twisted cube-on-cube epitaxial relationship, indicating high crystallinity for the BNT-ST and LNO films. The constituent elements in the BNT-ST/LNO/CeO2/YSZ structure showed no distinct diffusion between the layers. The BNT-ST epitaxial films demonstrated ferroelectric properties, but exhibited a high degree of leakage current density.