A very reliable multilevel YSZ resistive switching memory

Resistive Random Access Memory (RRAM) has emerged as a candidate for scaled memories [1]. To date, even though several metal oxide systems have been shown to exhibit resistive switching characteristics [2], a few of them have multilevel programming (MP) capability. Yttria Stabilized Zirconia (YSZ) which is widely used in electrochemistry applications has been largely unstudied, which is surprising given its high ionic mobility and excellent stability. Here, we demonstrate RRAM cells based on YSZ showing excellent performance in all metrics and we show that these devices have very reliable MP capability and in addition we demonstrate the use of an incremental step pulse programming scheme (ISPP) to realize an excellent balance between programming window, lifetime, and endurance. Finally, we demonstrate that oxygen vacancy (OV) based memories have better reliability than metallic filament based devices and are more suitable for multilevel use.