(a)
(b)
Figure 7: (a) Proposed physical mechanism for the origin of single and/or multiple conductive filaments (CFs) for Al/Al2O3/Al structure during the SET process (depending on the current compliance limit) and the effect that partial dissolution of this previously formed CF has on the progressive reduction of . For larger CC, multiple formation of CFs should be expected, with their composition being mostly based on metal ions [M+]. (b) Average surface roughness of the BE (after AFM) showing large surface roughness which is close to the physical Al2O3 thickness of the MIM device. High surface roughness would promote local electric-field enhancements.