Abstract
We report the first demonstration of a flexible one diode–one resistor (1D1R) resistive-switching (RS) memory cell capable of high-density crossbar array implementation at an extremely low cost. A Ti/TiO2/Pt diode with a large rectifying ratio and a stable Ni/HfO2/Pt unipolar RS memory element have been fabricated on a polyimide substrate using only room-temperature processes. No significant degradation of the rectifying ratio of the TiO2 diode and the cycling variations, retention, and read disturb immunity of the HfO2 memory was observed in the bending state. The series 1D1R cell shows highly reproducible unipolar RS because of the low reset current of the HfO2 memory, which greatly mitigates the adverse effect of diode series resistance. Furthermore, the 1D1R cell can effectively suppress read interference and realize a crossbar array as large as 512 kbit.