The properties of memristive structures based on (Co$_{40}$Fe$_{40}$B$_{20}$)$_{x}$(LiNbO$_{3}$)$_{100-x}$, nanocomposites synthesized on SiO$_{2}$/Si substrates

The structural features and current–voltage curves of metal/nanocomposite/metal sandwiches based on (Co$_{40}$Fe$_{40}$B$_{20}$)$_{x}$(LiNbO$_{3}$)$_{100-x}$ nanocomposites synthesized on SiO$_{2}$/Si substrates were studied. Samples were fabricated by ion-beam sputtering of a composite target, which provided an opportunity to produce nanocomposites with different compositions $x$ = 5–48 at % in a single cycle. The results of electron microscopy analysis revealed that the obtained nanocomposites consisted of metallic granules in an amorphous nonstoichiometric matrix. These granules were $\sim$ 2 – 3 nm in size and had a near-spherical (slightly elongated along the growth direction) shape. The local chemical composition of nanocomposite films was examined using X-ray photoelectron spectroscopy. The structures demonstrated resistive switching with the highest ratio of resistances in the low- and high-resistance states ($\sim$10) achieved at $x\sim$ 13 at%. The number of write/erase cycles exceeded 10$^4$. The observed effect of resistive switching is attributable to the influence of oxygen vacancies on the tunneling conductivity of contacts of percolation granule chains with one of the electrodes of the structure, which is separated by a highly oxidized layer from the nanocomposite.