Time-dependent electroforming in NiO resistive switching devices

Time-dependent electroforming phenomena in NiO capacitors are investigated. Different current-voltage characteristics between dc sweep mode and pulse mode indicate that electroforming is time-dependent process. Statistical time-dependent dielectric breakdown (TDDB) measurements show the exponential dependence of electroforming time on applied voltage, confirming that forming process is not a spontaneous process at some critical voltage, but an upsurge process resulting from stress-induced defects. The statistical TDDB analysis explains not only the nature of electroforming process but also the anomalous forming and large variations in forming parameters. (C) 2009 American Institute of Physics. [doi: 10.1063/1.3242337]