Modulation of the electrical characteristics on poly (3,4-ethylenedioxythiophene)-poly(styrenesulfonate)-based resistive random access memory device by the impact of top electrode materials

In this study, we fabricated polymer resistive random access memory (RRAM) devices using the conductive polymer poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) as an active layer and investigated the influence of various top electrode materials such as Cu, Al, and Ag on the modulation of the electrical characteristics of the RRAM. The fabricated RRAM devices with different top electrodes provided non-volatile bipolar resistive switching depending on the polarity of the applied voltage and current compliance (CC). Among these, RRAM devices with Ag top electrodes provided the best memory performance with a RON/ROFF ratio of > 102, > 140 cycles endurance, and a good retention time of ~104 s. In addition, multi-level cell switching was achieved by controlling the CC, which is desirable for neuromorphic computing applications. The analysis of the current voltage curves revealed that the Schottky emission was dominant in the high-resistance state. The proposed switching mechanism model was based on the formation and rupture of the conducting filaments by the electrochemical metallization effect.