Coumarin based non-volatile WORM device on a graphite coated paper substrate

During the past few years, a large number for organic small molecules (OSM) have been identified which may act as the active layer in resistive switching (RS) devices. In general, metal coated glass substrates are used as the bottom electrode in these devices which may contribute largely towards the global e-waste generation. This shortcoming may be addressed by utilizing paper substrate based non-metallic conductors like conductive polymers, graphene, graphite etc., In the present communication, we report a coumarin based RS device where a graphite-coated paper substrate has been utilized as the bottom electrode. The device exhibited write-once-read-many (WORM) type RS behaviour with an excellent memory window of the order of 10⁴. Moreover, the read endurance and the data retention time of the device have been found to be 10⁴ cycles and 2 h (measured), respectively. Furthermore, slope analysis of the I-V curve in double-logarithmic plot revealed that typical trap controlled SCLC mechanism is the key behind current conduction in the present device.