Resistive Switching Characteristics of Resistive Random Access Memory Based on a BaxSr1-xTiO3 Thin Film Grown by a Hydrothermal Method

Abstract

Resistive random access memory (RRAM) is one of the most promising candidates for emerging nonvolatile memory technology. Much effort has been devoted to exploring the resistive switching (RS) mechanism of multioxide films in the RRAM, especially perovskite oxide films. In this letter, we adopted a hydrothermal method to prepare a Ba <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">x</sub> Sr <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">1-x</sub> TiO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> barium strontium titanate (BST) thin film as a perovskite intermediate layer sandwiched between a top Pt electrode and a bottom TiN/Pt electrode in the RRAM cell. Based on current-voltage measurements, the result illustrated a typical bipolar RS characteristic, and with the increasing cycle count, the clockwise switching mode transformed to a counterclockwise switching mode. The double-logarithm current-voltage curves indicated different mechanisms, including ohmic conduction and space-charge-limited current, in both the set and reset states. A conductive filament (CF) model in which the RS behaviors are dominated by the movement of oxygen vacancies (V <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">O</sub> ) in the BST was adopted. In addition, the influence of the compliance current and maximum voltage is considered.