After 14,000 cycles, the reset resistance dropped rapidly, leading to the endurance failure by losing the set and reset resistance window. For the device with 8 nm TiO2, as shown in Figure 5f, the endurance capability keeps about 2,700 cycles before the presence of resistance disorder with a reset stuck failure mechanism. Good endurance characteristics (>104 cycles) was found in the cell

with 4-nm TiO2 buffer layer. The low resistance state maintained around 103 Ω magnitude, CH5183284 price and the high resistance state kept on 105 Ω level, indicating a satisfactory data resolution capability for random access memory application. The difference cyclic operation behavior shown in Figure 4b and Figure 5b,d,e suggested the different performance degradation processes for the device with and without TiO2 layer, which is currently under investigation. Among the various thicknesses of the TiO2 buffer layer, 4 nm was the most appropriate thickness that maximized the improvement with negligible

sacrifice of the other device performances, such as the reset/set resistance ratio, voltage window, and endurance. Conclusions This paper reports an efficient method for reducing the reset voltage and power of the conventional T-shaped PCRAM, which Proteasome inhibitor drugs has the potential to replace the current nonvolatile memories. We inserted TiO2 layer between phase change memory and bottom electrode to increase the utilization of the Joule heat and reduce the heat dissipation. Due to the suitable electrical resistivity and the low thermal conductivity of TiO2 film, the overall set resistance of the PCM cell will not be greatly increased, while the remarkably increased overall thermal resistance helps

to reduce the reset voltage. Authors’ information SS is an associate professor at the State Key Laboratory of Functional Materials for Informatics, Shanghai Institute of Micro-system and Information Technology, Chinese Academy of Sciences. Acknowledgments This work was supported by the National Key Basic Research Program of China (2010CB934300, 2011CB9328004, and 2011CBA00607), crotamiton the National Integrate Circuit Research Program of China (2009ZX02023-003), the National Natural Science Foundation of China (61006087, 61076121, 61176122, and 61106001), the Science and Technology Council of Shanghai (11DZ2261000 and 1052nm07000), and the Chinese Academy of Sciences (20110490761). References 1. Ovshinsky SR: Reversible electrical switching phenomena in disordered structures. Phys Rev Lett 1968, 21:1450–1453.CrossRef 2. Wuttig M, Yamada N: Phase-change materials for rewriteable data GDC0449 storage. Nat Mater 2007, 6:824–832.CrossRef 3. Kolobov AV, Fons P, Frenkel AI, Ankudinov AL, Tominaga J, Uruga T: Understanding the phase-change mechanism of rewritable optical media. Nat Mater 2004, 3:703–708.CrossRef 4. Lai S: Current status of the phase change memory and its future. In Electron Devices Meeting: December 8–10 2003, Santa Clara.