Atomic structure of conducting nanofilaments in TiO2 resistive switching memory.
Resistance switching in metal oxides could form the basis for next-generation non-volatile memory. It has been argued that the current in the high-conductivity state of several technologically relevant oxide materials flows through localized filaments, but these filaments have been characterized only indirectly, limiting our understanding of the switching mechanism. Here, we use high-resolution transmission electron microscopy to probe directly the nanofilaments in a Pt/TiO(2)/Pt system during resistive switching. In situ current-voltage and low-temperature (approximately 130 K) conductivity measurements confirm that switching occurs by the formation and disruption of Ti(n)O(2n-1) (or so-called Magnéli phase) filaments. Knowledge of the composition, structure and dimensions of these filaments will provide a foundation for unravelling the full mechanism of resistance switching in oxide thin films, and help guide research into the stability and scalability of such films for applications.
Kwon
Deok-Hwang
DH
Department of Materials Science and Engineering, Seoul National University, Seoul 151-744, Korea.
Kim
Kyung Min
KM
Jang
Jae Hyuck
JH
Jeon
Jong Myeong
JM
Lee
Min Hwan
MH
Kim
Gun Hwan
GH
Li
Xiang-Shu
XS
Park
Gyeong-Su
GS
Lee
Bora
B
Han
Seungwu
S
Kim
Miyoung
M
Hwang
Cheol Seong
CS
D003460:Crystallization; D004553:Electric Conductivity; D004563:Electrochemistry / Q000379:methods*; D005583:Fourier Analysis; D046529:Microscopy, Electron, Transmission; D049329:Nanostructures / Q000648:ultrastructure*; D036103:Nanotechnology / Q000379:methods*; D010087:Oxides / Q000737:chemistry*; D013499:Surface Properties; D014025:Titanium / Q000737:chemistry*
D010087:Oxides; D014025:Titanium