fig1
Figure 1. Illustration of the steps used to prepare the PBA sensor. (A) AlN sputtering deposition on Cu foil; (B) PVDF solution; (C) BTO-NP dispersion in PVDF; (D) PVDF+BTO-NP solution casting on AlN/Cu foil then spin coating and drying of PVDF+BTO-NP film; (E) wiring and PDMS sealing; and (F) Schematic diagram of PBA sensor. PBA: PVDF+BTO-NP/AlN; AlN: aluminum nitride; BTO-NP: BaTiO3 nanoparticle; PVDF: polyvinylidene fluoride.