Atomic layer deposition (ALD) offers nearly pinhole‐free, conformal, and with good thickness control, metal oxide nanometric thin films required for next‐generation memory devices. Here we report on the ALD of VOx thin films grown at about 100°C from a vanadium tri‐isopropoxide (VTIP) precursor, with water as the co‐reactant, followed by their post‐growth treatments, for potential applications in resistive switching (RS) devices. As‐grown VOx films are amorphous, and transform into polycrystalline layers upon annealing. Capacitor structures fabricated from amorphous VOx films show current‐voltage (I‐V) characteristics, interesting for RS applications. Depending on the electroforming conditions, bipolar‐type memory switching with a resistance ratio ROFF/RON > 103 is obtained, as well as a combination of memory and threshold switching. The latter is attractive for its highly non‐linear I‐V characteristics, which is attributed to the temperature‐induced insulator‐to‐metal transition (IMT) in vanadium dioxide.

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