Fig. 1
From: Surface diffusion-limited lifetime of silver and copper nanofilaments in resistive switching devices
Volatile and non-volatile switching of RS devices. a Schematic structure of a RS device based on Ag NWs. Bottom and top Au layers act as contact pads, Ag NWs act as effective bottom and top electrodes for the CF formation, and silk acts as insulating switching layer. b Sectional (left) and top planar (right) SEM views of the RS device. c Illustration of the metallic CF formation between two Ag NWs. A metallic CF can be formed in response to the application of a large voltage to the electrodes. In non-volatile switching, the CF can remain in the connected state for a relatively long time until another voltage pulse induces its disconnection. On the other hand, in the case of volatile switching, the CF retracts back to the electrodes immediately after set transition. d I–V characteristics for non-volatile switching for a high compliance current IC = 10 mA. When a positive sweep voltage is applied, the current increases sharply, indicating the formation of the metallic CF. The compliance current IC across the device controls the size of the formed CF. After the positive voltage sweeps back to zero, the device still remains in the low resistance state. As a negative voltage is applied, the device switches to the high resistance state indicating CF disruption. e I–V characteristics for volatile switching of the device at low IC. When a positive sweep voltage is applied, the current increases sharply indicating CF formation. However, the device quickly switches back to its original high resistance state after the forcing voltage is swept to zero. Bidirectional volatile switching is observed, as the application of a negative voltage also generates a metastable CF. f Probability for volatile switching (VS) as a function of IC, indicating the transition from volatile switching to non-volatile switching at increasing IC
