High Endurance Organic Resistive Switching Memory Based on 1,2-Dicyanobenzene and Polymer Composites

As the emerging data storage technology, organic resistive switching memory (ORSM) possess numerous superiorities as the substitute or complementation for the traditional Si-based semiconductor memory. Poly(3-hexylthiophene) (P3HT) has been widely used as the polymer donor component of ORSMs due to its advantages of high mobility and high chemical stability. Up to now, ORSM based on P3HT has achieved high on/off current ratio (Ion/off), but the endurance still needs to be improved. Herein, high endurance ORSMs based on 1,2-dicyanobenzene (O-DCB) and P3HT composite were fabricated by spin coating and thermally evaporating, which exhibited non-volatile and bipolar memory characteristics. ORSMs based on P3HT:15 wt.% O-DCB and P3HT:30 wt.% O-DCB exhibited an Ion/off of exceeding 104 and 103 respectively, and all of them exerted excellent endurance of 400 times, retention time of more than 105 s. The mechanism of the switching was explored by linear fitting of I-V curves and electrochemical impedance spectra (EIS). The results indicated that the filling and vacant process of the charge traps induced by O-DCB and the inherent traps in P3HT bulk led to the resistive switching effect. The negative or positive bias triggered the trapping and detrapping process, which led to the transforming of the conductive way of charges, resulting in the resistive switching effect. Excellent endurance of ORSMs was attributed to the uniform distribution of O-DCB in P3HT bulk because of the small molecular size and high solubility of O-DCB, which caused well-distributed and stable charge traps. On the other hand, the out-bound planarity of O-DCB molecular promoted the close interaction with the conjugated chains of P3HT. The study enlightens an effective strategy to carry out high-endurance ORSM and facilitates their electronic application in future.