Hydrothermal epitaxial growth and nonvolatile bipolar resistive switching behavior of LaFeO3-PbTiO3 films on Nb:SrTiO3(001) substrate

Abstract

Epitaxial LaFeO3-PbTiO3 (LFPTO) thin films were hydrothermally grown on the Nb-SrTiO3 (100) (NSTO) substrates with a thickness about 250 nm. As fabricated Pt/LFPTO/NSTO/Pt devices exhibit reversible bipolar resistive switching behavior. The resistance ratios between high resistance state and low resistance state exceed three orders of magnitude, which can be maintained over 6 h without observable degradation. It indicates that the Pt/LFPTO/NSTO/Pt devices reveal excellent data retention and endurance characteristics. The resistive switching mechanism of the device could be attributed to the trap-controlled space-charge-limited current conduction which is controlled by the localized oxygen vacancies in the films. Furthermore, variation of Pt/LFPTO Schottky junction depletion thickness and barriers height modulated by oxygen vacancies at Pt/LFPTO interface was suggested to be responsible for the resistance switching behaviors of the devices.