Low operation voltage transparent resistive random access memory (T-RRAM) based on ultrathin a-TiOx films and its resistive switching characteristics

A fully transparent resistive random access memory (T-RRAM) device based on an ultrathin a-TiO_x storage layer sandwiched between the top ITO and bottom FTO electrodes (ITO/a-TiO_x/FTO) was fabricated on the glass substrate. The memory device exhibited not only good optical transmittance (~80%) but also a bipolar resistive switching characteristic with low operation voltage (-0.5V/+1V), low operation current (500μA), high R_OFF/R_ON ratio (>100), reasonable endurance (>10² cycles), and retention characteristics (10⁴ s). The resistive switching mechanism could be explained by the formation and rupture of the oxygen vacancies induced conductive filament near ITO and a-TiO_x interface. Our devices demonstrated the great potential for future transparent electronic applications.