Regensburg 2013 – scientific programme
Parts | Days | Selection | Search | Updates | Downloads | Help
DF: Fachverband Dielektrische Festkörper
DF 21: Resistive Switching (jointly with DF, KR, HL)
DF 21.7: Talk
Friday, March 15, 2013, 11:15–11:30, H32
Creating an Oxygen Gradient in Nb2O5 by Argon Irradiation for Resistive Switching Memory — •Helge Wylezich1, Hannes Mähne1, Daniel Blaschke2, Stefan Slesazeck1, and Thomas Mikoljiack1 — 1NamLab gGmbH, Nöthnitzer Str. 64, D-01187 Dresden — 2Helmholtz-Zentrum Dresden-Rossendorf, D-01314 Dresden
It is common knowledge that an oxygen gradient is mandatory for bipolar resistive switching [1]. We confirmed this by investigations of thin films with Nb2O5 as switching layer. Samples with two inert Pt electrodes are nearly symmetric and do not show bipolar resistive switching behavior. Replacing one Pt electrode with a reactive one – for example Al or Nb – results in an unsymmetrical device. These samples could be switched reproducible. It is also possible to create an oxygen gradient by depositing a stack of two different niobium oxide layers. While the first layer consists of stoichiometric Nb2O5 the second layer is sputtered substoichiometric [2].
A new approach is to get an oxygen gradient by irradiating the oxide layer with argon. Two effects appear: The argon sputters the surface of the Nb2O5 layer and so the oxide thickness decreases. Because the Nb-atoms are heavier than the O-atoms, the oxygen sputter rate is higher and the surface becomes niobium rich. The investigated samples consist of a Pt-Nb2O5-Pt stack. The oxide layer was irradiated by different Ar-doses before top electrode deposition. At the highest dose Φ = 3e16 cm−2 the resulting oxygen gradient enables resistive switching.
[1] Bertaud et al. (TSF 520, 2012)
[2] Mähne et al. (MEMCOM Workshop 2012)