Bipolar Resistive Switching Properties of Hf_(0.5)Zr_(0.5)O_2 Thin Film for Flexible Memory Applications

摘要

An Au/Ni/Hf_(0.5)Zr_(0.5)O_2/Au flexible memory device fabricated on a polyethylenernterephthalate substrate was studied for flexible resistive random accessrnmemory applications. A typical bipolar resistive switching behavior wasrnrevealed with an OFF/ON ratio of approximately 15. The reproducibility andrnuniformity were investigated using 100 repetitive write/erase cycles. Thernretention property did not degrade for up to 5×10~4 s, and the resistivernswitching properties did not degrade even under bending conditions, whichrnindicated good mechanical flexibility. The current–voltage characteristics ofrnthe memory device show a Poole–Frenkel emission conduction mechanism inrnthe high-voltage region in the high-resistance state, while in the low-voltagernregion, the Ohmic contact and space charge limit current responded to thernlow-resistance state and high-resistance state, respectively. Combined withrnthe conductance mechanism, the resistive switching behavior is attributed tornconductive filaments forming and rupturing due to oxygen vacanciesrnmigrating under the external driving electric field.