TY  - JOUR
AU  - Skaja, Katharina
AU  - Bäumer, Christoph
AU  - Peters, Oliver
AU  - Menzel, Stephan
AU  - Moors, Marco
AU  - Du, Hongchu
AU  - Bornhöfft, Manuel
AU  - Schmitz, Christoph
AU  - Feyer, Vitaliy
AU  - Jia, Chun-Lin
AU  - Schneider, Claus Michael
AU  - Mayer, Joachim
AU  - Waser, Rainer
AU  - Dittmann, Regina
TI  - Avalanche-Discharge-Induced Electrical Forming in Tantalum Oxide-Based Metal-Insulator-Metal Structures
JO  - Advanced functional materials
VL  - 25
IS  - 46
SN  - 1616-301X
CY  - Weinheim
PB  - Wiley-VCH
M1  - FZJ-2015-07533
SP  - 7154–7162 
PY  - 2015
AB  - Oxide-based metal–insulator–metal structures are of special interest for future resistive random-access memories. In such cells, redox processes on the nanoscale occur during resistive switching, which are initiated by the reversible movement of native donors, such as oxygen vacancies. The formation of these filaments is mainly attributed to an enhanced oxygen diffusion due to Joule heating in an electric field or due to electrical breakdown. Here, the development of a dendrite-like structure, which is induced by an avalanche discharge between the top electrode and the Ta2O5-x layer, is presented, which occurs instead of a local breakdown between top and bottom electrode. The dendrite-like structure evolves primarily at structures with a pronounced interface adsorbate layer. Furthermore, local conductive atomic force microscopy reveals that the entire dendrite region becomes conductive. Via spectromicroscopy it is demonstrated that the subsequent switching is caused by a valence change between Ta4+ and Ta5+, which takes place over the entire former Pt/Ta2O5-x interface of the dendrite-like structure.
LB  - PUB:(DE-HGF)16
UR  - <Go to ISI:>//WOS:000366503700005
DO  - DOI:10.1002/adfm.201502767
UR  - https://juser.fz-juelich.de/record/279651
ER  -