UNASSIGNED: Filamentary-based @entity8369 resistive memory is considered as a disruptive technology for non-volatile data storage and reconfigurable logic. Currently accepted models explain the resistive switching in these devices through the presence/absence of a @entity713 ( @entity713 ) which is described as a reversible nanosized valence-change in an @entity8369 material. During device operation, the @entity713 cycles billion of times at sub-ns speed, using few tens of   A as operating current and thus determines the whole device's performance. In spite of its importance, the @entity713 observation is hampered by the small filament size and its minimal compositional difference with the surrounding material. Here we show an experimental solution to this problem and provide the three-dimensional characterization of the @entity713 in a scaled device. For this purpose we have recently developed a tomography technique which combines the high spatial resolution of scanning probe microscopy (SPM) with sub-nm precision in material removal. Leading to a true 3D-probing metrology concept. We locate and characterize in three-dimensions the nanometric volume of the @entity713 in state-of-the-art bipolar @entity8369 -based devices. Our measurements demonstrate that the switching occurs through the formation of a single @entity713 . The filaments exhibit sizes below 10 nm and present a constriction near the @entity26 -inert electrode. Finally, different @entity5526 are observed as function of the programming current, providing evidence for the filament's nature as a defects modulated quantum contact.

Imaging the three-dimension conductive channel in filamentary-based XXXX resistive switching memory.

@entity713 :: ('MESH:D054537', 'Disease') :: ['conductive filament', 'CF'] @entity26 :: ('MESH:D010100', 'Chemical') :: ['oxygen'] @entity5526 :: ('MESH:D003877', 'Disease') :: ['atomic-size contacts'] @entity8369 :: ('CHEBI:25741', 'Chemical') :: ['oxide']
@entity8369 :: (CHEBI:25741,Chemical) :: ['oxide']
