Improved endurance of resistive switching TiO2 thin film by hourglass shaped Magneli filaments

A modified biasing scheme was adopted to improve the electrical endurance characteristics of conducting filamentary resistive switching (RS) in a Pt/TiO2/Pt RS cell. The modified bias scheme included the application of bias voltages with alternating polarity, even though RS proceeds in non-polar mode, which results in the stable distribution of each resistance states as well as improved endurance. This was attributed to the minimized consumption of oxygen ions in the TiO2 film, which can be induced by the formation of hourglass-shaped conducting filament (HSCF). The presence of a HSCF was confirmed by high-resolution transmission electron microscopy. (C) 2011 American Institute of Physics. [doi:10.1063/1.3600784]This study was supported by the National Research Program for the Nano Semiconductor Apparatus Development sponsored by the Korea Ministry of Knowledge and Economy, the Convergent Research Center program (Grant No. 2010K000977), and World Class University program through the National Research Foundation of Korea funded by the Ministry of Education, Science, and Technology (Grant No. R31-2008-000-10075-0)