Abstract:

The vacuum thermal evaporation of KSCN onto the surface of a Ag electrode results in a AgK2(SCN)3 composite film through an interfacial reaction between the Ag and KSCN films. Visible spectroscopy, X-ray photoelectron spectroscopy (XPS), Raman spectroscopy, and X-ray diffraction (XRD) were used to investigate the film. The Al/AgK2(SCN)3/Ag device exhibited reversible electrical bistability with a resistance ratio of 106 and it was successively operated in a“write-read-erase-read”mode. The reversible writing and erasing performance of the device is attributed to the formation and rupture of conducting channels through the AgK2(SCN)3 composite layer. By fitting the currentvoltage curves, the low-and high-resistance states are shown to follow ohmic conduction and space charge limited current conduction, respectively. We suggest that the annihilation of conducting channels is caused by the electrochemical ionization together with the Joule heating effect.

Key words: Electrochemical ionization, Electrical bistable states, Conducting channel, Interface reaction, Vacuum thermal evaporation, Joule heating effect