Resistive switching mechanisms in memristor structures based on nonstoichiometric silicon nitride layers

The electrophysical properties and the resistive switching effect of the Ni/SiN x /p + Si/Ni memristor structure are investigated. Silicon nitride films with a thickness of ~40–60 nm were deposited in inductively coupled plasma from a SiH 4 – N 2 –Ar mixture at [SiH 4 ]/[N 2 ] ratios of 2.19 and 2.55, which ensured the formation of SiN x with an excess of Si compared to stoichiometry. To investigate the effect of thermal annealing on the resistive properties of SiN x , one of the wafers with a nitride film was annealed using rapid thermal annealing (RTA, 1200 °C, 3 minutes in Ar). The resistive switching effect was observed when applying a voltage from −4 to +10 V for test structures based on nitride films with refractive indices of 2.34 and 2.5. It is shown that the conductivity and charge transport mechanism in SiN x films with resistive properties depend on the deposition conditions and subsequent heat treatment. Possible mechanisms of resistive switching are discussed.