Redox-Based Bi-Layer Metal Oxide Memristive Devices

In a memristor or a so-called memristive device, the resistance state depends on the previous charge flow through the device. The new resistance state is stored and classifies a memristor as a non-volatile memory device. This likewise unique and simple feature qualifies memristive devices as attractive compartments with regard to the development of a universal memory and beyond von Neumann computing architectures, including in-memory computing and neuromorphic circuits. In this chapter, we present studies on two kinds of bi-layer metal oxide memristive devices with the layer sequences Nb/NbO $$_{\textrm{z}}$$z /Al $$_2$$2 O $$_3$$3 /Nb $$_{\textrm{x}}$$x O $$_{\textrm{y}}$$y /Au and TiN/TiO $$_\textrm{x}$$x /HfO $$_\textrm{x}$$x /Au, either prepared by reactive DC-magnetron sputtering, etching and optical lithography. It is shown that the memristive properties of such devices can be engineered, which enables tailoring of the memristive devices for particular applications.