Analysis and optimization of read/write reliability for 12F~2 cross-point ultra-fast phase change memory

摘要

Phase change memory (PCM) device using a diode as selector exhibits a high level of integration based on 40 nm process, but it still has some reliability problems, such as read disturbance and writing performance. In this paper, we test and improve the read/write reliability of one diode and one resistor (1D1R) structure cell in array with cell size of 12F(2) (0.16 mu m x 0.12 mu m). The 1D1R device has good performance with ultra-high speed (20 ns) and low programming voltage (3.3 V). The cell programmed by current pulse has a better performance than that of voltage operation in amorphous state with respect to read disturb immunity. The ratio of reset/set resistance can be improved by choosing appropriate parameter of write operation. In addition, the endurance characteristics of the devices are investigated. The optimization in read/write operation guarantee that 1D1R device can satisfy the requirements for the high-speed and high-density applications.