Reliability study of organic nonvolatile resistive memory at elevated temperatures

Abstract

In this study, nonvolatile organic memory devices were fabricated by using PI:PCBM (polyimide (PI) and 6-phenyl-C61 butyric acid methyl ester (PCBM) as an active memory material with Al/PI:CPBM/Al structure. As changing temperature from room temperature to 470 K, PI:PCBM organic memory devices showed good nonvolatile memory properties in terms of distribution of ON state current and OFF state current, threshold voltage of OFF state to ON state transition, retention, and endurance. These organic memory devices exhibited excellent ON/OFF ratio (ION/IOFF >103) through more than 200 times ON/Off switching cycles, and maintained ON/OFF states for longer than 104 seconds without showing any serious degradation under the measurement temperature up to 470 K. The structural robustness against thermal stress was confirmed through TEM cross-sectional image and AFM image of active layer after retention test at 470 K during 10,000 seconds. This study demonstrated that the operation of organic memory devices under high temperatures was able to be controlled by the parameters which was already used for room temperature, and that the structure of organic memory devices was maintained during thermal stress. These results may make it possible the utility of nonvolatile organic memory devices for high temperature environments.