Resistive switching characteristics of Cu/ZnO _0.4S _0.6/Al devices constructed on plastic substrates

In this study, Cu/ZnO _0.4S _0.6/Al devices are fabricated on plastic substrates using the sputtering method at room temperature. The ratio of O/S in the zinc oxysul?de thin ?lm is con?rmed to be 0.4/0.6 from the Auger depth pro?ling. The Cu/ZnO _0.4S _0.6 /Al devices show unipolar resistive switching behaviors and the ratio of the measured resistance in the low-resistance state (LRS) to that in the high-resistance state (HRS) is above 10 ⁴. The conduction mechanism of the LRS is governed by Ohm's law. On the other hand, in the HRS, the conduction mechanism at low voltages is controlled by Ohm's law, but that at high voltages results from the Poole-Frenkel emission mechanism. The Ohmic and Poole-Frenkel conduction mechanisms observed in the LRS and HRS support the ?lament model of unipolar resistive switching. The memory characteristics of the Cu/ZnO _0.4S _0.6/Al devices are retained for 10 ⁴ sec without any change.