Thermally Stable Transparent Resistive Random Access Memory based on All-Oxide Heterostructures

An all-oxide transparent resistive random access memory (T-RRAM) device based on hafnium oxide (HfOx) storage layer and indium-tin oxide (ITO) electrodes is fabricated in this work. The memory device demonstrates not only good optical transmittance but also a forming-free bipolar resistive switching behavior with room-temperature R-OFF/R-ON ratio of 45, excellent endurance of approximate to 5 x 10(7) cycles and long retention time over 10(6) s. More importantly, the HfOx based RRAM carries great ability of anti-thermal shock over a wide temperature range of 10 K to 490 K, and the high R-OFF/R-ON ratio of approximate to 40 can be well maintained under extreme working conditions. The field-induced electrochemical formation and rupture of the robust metal-rich conductive filaments in the mixed-structure hafnium oxide film are found to be responsible for the excellent resistance switching of the T-RRAM devices. The present all-oxide devices are of great potential for future thermally stable transparent electronic applications.