The influence of interface contact condition on resistive switching of Au/Nb:SrTiO3 heterojunctions

The influence of the interface contact condition on the resistive switching (RS) effects of metal/Nb:SrTiO3 heterojunctions was investigated. Two Au/Nb:SrTiO3 samples with or without in situ substrate cleaning treatment were fabricated. Through comparative analysis of I–V hysteresis and switching performance, it was observed that the RS effect in the heterojunction formed by the in situ cleaned Nb:SrTiO3 substrate was significantly weakened. In addition, the SEM image demonstrates intimate contact between metal and the in situ cleaned substrate. In contrast, the untreated Au/Nb:SrTiO3 interface exhibits poor contact. The poor contact, as confirmed by interface AFM and CAFM images, is responsible for the resistive switching observed. Our research provides an innovative approach to elucidating the mechanism of the resistive switching effect, which will pave the way for better application of the device.