Recently, ferroelectric tunnel junctions (FTJs) have attracted great attention due to promising applications in non-volatile memories. In this study, we report high-temperature tunneling electroresistance (TER) of metal/ferroelectric/semiconductor FTJs. Hysteretic resistance-voltage loops are observed in the Pt/BaTiO3/Nb:SrTiO3tunnel junction from 300 to 513 K due to the modulation of interfacial Schottky barrier by polarization switching in the 4 u.c.-thick BaTiO3barrier via a ferroelectric field effect. The Pt/BaTiO3/Nb:SrTiO3device exhibits a giant ROFF/RONresistance ratio of ∼3 × 105at 383 K and maintains bipolar resistance switching up to 513 K, suggesting excellent thermal endurance of the FTJs. The temperature-dependent TER behaviors are discussed in terms of the decrease of polarization in the BaTiO3barrier, and the associated junction barrier profiles are deduced by transport and capacitance analyses. In addition, by extrapolating the retention time at elevated temperature in an Arrhenius-type relation, activation energy of ∼0.93 eV and room-temperature retention time of ∼70 years can be extracted.
ASJC Scopus subject areas
- Physics and Astronomy (miscellaneous)