Nonvolatile Memristive Switching Characteristics of TiO$_{\bm 2}$ Films Embedded With Nickel Nanocrystals

Nickel nanocrystal (Ni-NC)-embedded titanium dioxide films have been deposited for nonvolatile resistive switching memory devices. The polycrystalline behavior of the films has been observed from the X-ray diffraction spectra. Tiny isolated Ni-NCs with an average size of 4 nm are observed for the 1000 °C, 5-min annealed samples. Stable, bipolar, nonvolatile, and bistable resistive switching states are observed for the optimized annealed Ni-NC-embedded devices with a low SET and RESET voltage of 0.8 and −0.2 V, respectively. A high resistance ratio (>10
$^3$
), good stability, and retention properties are observed for the nanocrystal sample. The role of thin Ni-NC layer on memory switching stability is discussed.