Highly transparent bipolar resistive switching memory with In-Ga-Zn-O semiconducting electrode in In-Ga-Zn-O/Ga2O3/In-Ga-Zn-O structure

In this work, based on wide bandgap Ga2O3 films, we demonstrated a fully transparent bipolar resistive random access memory (RRAM) device with very high average transmittance of 91.7% in the visible region. The semiconducting In-Ga-Zn-O (IGZO) films were used as symmetric electrodes to reduce sneak current. Different I-V performance will introduce a change in the overall oxygen vacancy distribution by an opposite polarity of electroforming voltage. The temperature dependent of I-V characteristics will be fitted to the hopping conduction mechanism for both of the high-resistance states (HRS) and low-resistance states (LRS) with semiconducting nature. The activation energy and trap spacing of LRS were lower and shorter than that of HRS. A model of resistive switching mechanism related to correlated barrier hopping theory has been proposed for the fully transparent IGZO/Ga2O3/IGZO RRAM device.