Dynamics of electroforming in binary metal oxide-based resistive switching memory

The onset of localized conduction in TaOx- and TiOx-based resistive switching devices during forming has been characterized. The novel temperature and voltage dependencies of forming times were extracted with pulsed forming experiments that spanned five orders of magnitude in time and showed three different regimes of electroforming. A universal field-induced-nucleation theory which included self-heating effects was used to explain a strong reduction in forming voltage with increasing forming time over all observed regimes of electroforming. It was shown that the effective activation energy for the incubation time changes inversely proportional with the electric field. A diameter of the volatile filament that precedes forming was estimated at ∼1 nm.