Resistive switching effect in TaN/HfO$_x$/Ni memristors with a filament formed under local electron-beam crystallization

The influence of an intense electron beam on a nonstoichiometric oxide HfO$_x$ ($x \approx 1.8$) layer of a TaN/HfO$_x$/Ni memristor on its electrophysical properties is studied. It is found that the crystalline $h$-Hf, $m$-HfO$_2$, $o$-HfO$_2$, and $t$-HfO$_2$ phases are formed in the HfOx film under this impact. It is established that memristors demonstrate resistive switching at certain electron fluence values. At the same time, such memristors have resistive switching voltages several times lower than those of unirradiated memristors. In addition, they exhibit a multiple decrease in the spread of resistive switching voltages, as well as resistances in low- and high-resistance states. The current–voltage curves of the obtained memristors indicate that the charge transport in them is described by the space-charge-limited current mechanism.