Improvement of memristive switching of Pb(Zr0.52Ti0.48)O3/Nb:SrTiO3 heterostructures via La doping

The ferroelectric memory with superior stability and high operating speed has broad development prospects in areas such as neural computing and information storage. An effective strategy to improve the performance of the resistive switching (RS) of the ferroelectric memory is to improve the conductivity of ferroelectric thin films while maintaining their ferroelectric properties, because there is a competition between ferroelectric properties and conductivity in the RS behavior. Herein, we prepared La-doped Pb(Zr0.52Ti0.48)O3 (PLZT) thin films on the Nb:SrTiO3 (NSTO) substrate. By controlling La concentration, a compromise between ferroelectricity and conductivity was achieved. The RS on/off ratio reached 2.6 × 104 doped with 2 mol% La. Moreover, the conduction mechanism changes from the Schottky emission controlling PZT/NSTO interface to the coexistence of Schottky emission and space charge-limited mechanism in the PLZT/NSTO heterostructures. The results reveal that the effective matching of the ferroelectricity and conductivity of ferroelectric thin films is necessary for obtaining high RS on/off ratio, which is helpful to the accurate design of high-performance ferroelectric memory devices. •The RS on/off ratio reached about 2.6 × 104 in the PLZT/NSTO heterostructures doped with 2 mol% La.•The conduction mechanism changes from the Schottky emission controlling PZT/NSTO interface to the coexistence of Schottky emission and space charge-limited mechanism in the PLZT/NSTO heterostructures due to the introduction of oxygen vacancies.