Effects of the electroforming polarity on bipolar resistive switching characteristics of SrTiO3-δ films

Department of Materials Science and Engineering, Nanjing University, Nanjing 210093, People’s Republic of China
Applied Physics Letters (Impact Factor: 3.3). 10/2010; 97(11):112101 - 112101-3. DOI: 10.1063/1.3488810
Source: IEEE Xplore


The effects of the electroforming polarity on the bipolar resistive switching characteristics in SrTiO 3-δ thin films have been investigated. The conduction mechanisms of high resistance state and low resistance state are Poole–Frenkel emission and tunneling, respectively. The temperature dependences of the resistance at high and low resistance state are both semiconductorlike. The impact of the polarity of the electroforming voltage on the resistive switching mechanism and the distribution of defects was discussed. A simple model describing the combination of bulk and the interface effect was proposed to explain the resistive switching in this material.

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