Memristor Behavior in Epitaxial Cu_2-xSe Thin Films

Materials with memristor properties are currently of interest because of their applications in neuromorphic circuitry and resistive switching devices. Memristors are suitable for neuromorphic circuitry due to their low energy consumption, high density, and CMOS compatibility. Additionally, low leakage current and high on-to-off current ratios are essential for efficient devices. Non-stoichiometric copper selenide is a promising material that exhibits the above behavior, where the resistive switching is believed to be attributed to the ionic conductivity of copper ions [1]. We will present the room temperature memory resistive behavior of epitaxially grown Cu_2-xSe on Al₂O₃ using Molecular Beam Epitaxy (MBE). The films were characterized using Reflection High Energy Electron Diffraction (RHEED), X-Ray Diffraction (XRD), and Atomic Force Microscopy (AFM). Al interdigitated contacts were used to perform current-voltage (I-V) measurements. The (I-V) measurements showed resistive switching of Cu_2-xSe at room temperature with over five orders of magnitude of on-off current ratios.

1. 1. Rehman at el. Appl. Phys. 50 (2017) 135301 (8pp)