Resistive switching properties of multiferroic YMnO₃

Multiferroics, materials with simultaneous presence of any two or more of primary ferroic orderings in the same phase have gained a great attention both from scientists and industry [1]. Multiferroism gives an opportunity for a development of new materials and concepts for multifunctional devices. Presented work investigates the resistive switching properties of YMnO₃, known as an improper multiferroic [2]. Thin YMnO₃ films were grown by pulsed laser deposition on Si substrates with Ti/Pt bottom electrode at 800°C and varying oxygen partial pressure. Characterization of as-grown samples by X-ray diffraction and scanning electron microscopy was followed by determination of electrical properties of films in metal-insulator-metal (MIM) configuration. Results indicate a non-volatile unipolar resistive switching with high resistance ratio of high over low resistance state (>10^4). Switching mechanism is ascribed to the formation and rupture of conductive paths in the YMnO₃ films upon applied current. In addition, the role of film microstructure and defect formation/distribution resulting from different growth conditions and its effect on the resistive switching behavior are discussed.

[1] N.A. Spaldin et al., Physics Today 63 (2010) 38.
[2] B.B. Van Aken et al., Nature Mater. 3 (2004) 164.