  Electrical switching and rectifying properties of the metal-VO2-Si
structures, on both p-type and n-type silicon, with vanadium dioxide films
obtained by an acetylacetonate sol-gel method, are studied. The switching
effect is shown to be due to the semiconductor-to-metal phase transition (SMPT)
in vanadium dioxide. The shift of the switching threshold voltage, accompanied
by the memory effect, in forward bias of the p-Si-VO2 anisotype heterojunction
is observed. To explain this effect, a model is proposed which suggests the
existence of an additional series resistance associated with a channel at the
VO2/Si interface, where a SiOx layer forms during the VO2 deposition process.
This resistance is responsible for both threshold switching characteristics,
and the memory effect, and the oxygen ion electromigration process is shown to
underlie this effect. Potential applications of the observed phenomena,
combining the effects of ReRAM and SMPT, in oxide electronics are discussed.
