Mechanical strain effects on resistive switching of flexible polymer thin films embedded with ZnO nanoparticles

The resistive switching of polymer films embedded with nanoparticles (NPs) offers the promise for future flexible and transparent memory applications. Herein, we studied the interfacial effects on resistive switching of polymer film embedded with ZnO NPs under various mechanical stimuli. Bipolar resistive switching withON/OFF ratio of more than 10(3) was obtained, which can keep stable for more than 10(6) s. The vacuum spray-deposited samples show better bending endurance than that of the spin-coated ones due to the optimal film morphology and evenly distributed ZnO NPs. The transport mechanism translates from the trap-controlled space charge limited conduction to the Ohmic behavior after severe bending, indicting a decrease in the capture efficiency of interfacial energy traps. Based on the finite element analysis and the quantum chemical calculation, we show that ZnO NPs may act as stress singularities in the polymer matrix, and interfacial crack and delamination behaviors may occur after repetitive bending. Such cracks can hinder the carriers transport and lead to deteriorative switching performance.