Self-Limited Switching in Ta2O5/TaOx Memristors Exhibiting Uniform Multilevel Changes in Resistance

To facilitate the development of memristive devices, it is essential to resolve the problem of non-uniformity in switching, which is caused by the random nature of the filamentary switching mechanism in many resistance switching memories based on transition metal oxide. In addition, device parameters such as low- and high-state resistance should be regulated as desired. These issues can be overcome if memristive devices have switching limits for both the low- and high-resistance states and if their resistance values are highly controllable. In this study, a method termed self-limited switching for uniformly regulating the values of both the low- and high-resistance states is suggested, and the circuit configuration required for the self-limited switching is established in a Ta2O5/TaOx memristive structure. A method of improving the uniformity of multi-level resistance states in this memristive system is also proposed.