scholarly journals Composition profiles across MIMs for resistive switching studied by EDS and EELS

2014 ◽  
Vol 70 (a1) ◽  
pp. C1456-C1456
Author(s):  
Florian Hanzig ◽  
Josef Veselý ◽  
Mykhaylo Motylenko ◽  
Astrid Leuteritz ◽  
Hannes Mähne ◽  
...  
Keyword(s):  
Transition Metal ◽  
Metal Oxides ◽  
Oxygen Content ◽  
Data Storage ◽  
Resistive Switching ◽  
Transition Metal Oxides ◽  
Atomic Scale ◽  
Edge Structure ◽  
Transmission Electron ◽  
Metal Insulator Metal

Resistive switching in MIM (metal-insulator-metal) stacks is an effect that enables a promising data storage technology which is able to overcome the size limitations of conventional non-volatile memories. The resistive switching effect was already demonstrated for several binary as well as ternary transition metal oxides (TiO2, NiO, SrTiO3, Nb2O5) [1,2]. The current models of the switching mechanisms suggest the important role of defects like oxygen vacancies [3]. Here, we report on the local structural and electronic properties of transition metal oxides embedded in MIM stacks that were obtained by using transmission electron microscopy and electron spectroscopy. We focus on the development of the stoichiometry across the MIM stack for amorphous and partial crystalline niobium oxides. Therefore, electron energy loss spectra (EELS) as well as the energy dispersive X-ray spectra (EDS) were collected on the atomic scale utilizing a nanometer probe in the scanning transmission electron microscope (STEM). The differences in the oxygen content among the electrodes and the concentration profiles at the metal/oxide interfaces in particular were investigated in dependence on the preparation method and on the electrode material. Besides, focusing on the electron loss near edge structure (ELNES) of the oxygen K edge we employed simulations using FEFF9 to describe the modifications of the electronic structure with variations in the oxygen content.

scholarly journals Mechanism for bipolar resistive switching in transition-metal oxides

2010 ◽  
Vol 81 (11) ◽  
Author(s):  
M. J. Rozenberg ◽  
M. J. Sánchez ◽  
R. Weht ◽  
C. Acha ◽  
F. Gomez-Marlasca ◽  
...  
Keyword(s):  
Transition Metal ◽  
Metal Oxides ◽  
Resistive Switching ◽  
Transition Metal Oxides ◽  
Bipolar Resistive Switching

OxygenKx-ray-absorption near-edge structure of alkaline-earth-metal and 3d-transition-metal oxides

1987 ◽  
Vol 36 (17) ◽  
pp. 9241-9246 ◽  
Author(s):  
Shun-ichi Nakai ◽  
Tsutomu Mitsuishi ◽  
Hidenao Sugawara ◽  
Hideki Maezawa ◽  
Tokuo Matsukawa ◽  
...  
Keyword(s):  
Transition Metal ◽  
Metal Oxides ◽  
Transition Metal Oxides ◽  
Alkaline Earth ◽  
Earth Metal ◽  
Alkaline Earth Metal ◽  
Edge Structure

Valence Mapping of Particulate 3D-Transition Metal Oxides Using Energyfiltered Transmission Electron Microscopy

2000 ◽  
Vol 6 (S2) ◽  
pp. 176-177
Author(s):  
R.M. Stroud ◽  
J.H. Scott
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Transition Metal ◽  
Metal Oxides ◽  
Transition Metal Oxides ◽  
Data Extraction ◽  
Mixed Valence ◽  
Charge Localization ◽  
Transmission Electron ◽  
Critical Issues

Particulate, mixed-valence transition metal oxides are frequently used for battery, catalytic and magnetic applications. For example, the Li ion exchange battery exploits charge transfer of mixed Mn+3, Mn+4 materials. Charge localization and phase separation, especially at particle surfaces, are critical issues for determining the materials’ useful properties, be it catalytic activity or saturation magnetization. The ability to image the charge localization and correlate this with crystallographic information would be extremely useful in the study of this class of materials. Using energy-filtered transmission electron microscopy (EFTEM), valence maps of Mn and Co with a ∼ 2 nm scale have been obtained for bulk samples. In principal this technique can de directly extended to the case of particulate samples, however there are some additional experimental challenges, such as thickness and edge effects, that must be addressed. We demonstrate here the feasibility of valence mapping of particulate samples, and discuss the factors that limit quantitative data extraction from the maps.

Reversible Photoredox Processing of Transition Metal Oxides

1995 ◽  
Vol 397 ◽  
Author(s):  
R. Martin Villarica ◽  
Fazio Nash ◽  
J. Chaiken ◽  
Joe Osman ◽  
Rebecca Bussjager
Keyword(s):  
Transition Metal ◽  
Metal Oxides ◽  
Data Storage ◽  
Transition Metal Oxides ◽  
Chemical Process ◽  
Green Laser ◽  
Optical Data Storage ◽  
Optical Data ◽  
Storage Media ◽  
Laser Sources

ABSTRACTWe describe a novel laser chemical process having potential for optical data storage and processing applications. Reversible oxygen exchange involving WO3, using readily available laser sources offers improved durability and versatility over existing erasable optical data storage media. Being interconvertable using heat and blue-green laser sources, the well known yellow WO3 and blue W2O5 can function as erased and written states.

Resistive Switching Memory Devices Composed of Binary Transition Metal Oxides Using Sol−Gel Chemistry

Langmuir ◽  
2009 ◽  
Vol 25 (8) ◽  
pp. 4274-4278 ◽  
Author(s):  
Chanwoo Lee ◽  
Inpyo Kim ◽  
Wonsup Choi ◽  
Hyunjung Shin ◽  
Jinhan Cho
Keyword(s):  
Transition Metal ◽  
Metal Oxides ◽  
Resistive Switching ◽  
Transition Metal Oxides ◽  
Sol Gel ◽  
Memory Devices ◽  
Resistive Switching Memory ◽  
Switching Memory

Transition metal oxides revisited: ELNES of metal L2,3 and oxygen K edges

1989 ◽  
Vol 47 ◽  
pp. 390-391
Author(s):  
Ondrej L. Krivanek ◽  
James H. Paterson ◽  
Helmut R. Poppa ◽  
P. Rez
Keyword(s):  
Transition Metal ◽  
Energy Loss ◽  
Metal Oxides ◽  
Chromium Oxide ◽  
Transition Metal Oxides ◽  
Thin Metal Film ◽  
Edge Structure ◽  
Thin Oxide Films ◽  
Fine Structures ◽  
Electron Energy Loss

When examined at 0.5 eV or better energy resolution by electron energy loss spectroscopy (EELS), many inner shell loss edges begin to show new fine structures. Recently, we have been able to acquire inner shell loss spectra routinely at about 0.4 eV resolution, using the Gatan PEELS™ on the VG HB501 STEM. We have therefore decided to reinvestigate the energy-loss near-edge structure (ELNES) of oxygen K and metal L2,3 edges in first row transition metal oxides.Figure 1 shows the metal L2,3 edges from vanadium oxide, chromium oxide, manganese oxide, iron oxide, cobalt oxide, nickel oxide, and copper oxide. Except for the chromium oxide sample, which was prepared by crushing and dispersing grains of crystalline Cr2O3, samples were made by vapor-depositing a thin metal film onto rock salt, heating it in air at about 400° C while still on the substrate, and subsequently floating it off. The resultant thin oxide films were from the same sample batches as those used for the EELS Atlas, where they were identified as VOx, MnO2, Fe2O3, CoO, NiO, and CuO.

Sign in / Sign up

Export Citation Format

Share Document