Preparation And Resistive Switching Behavior Of Au-PbZr_0.4Ti_0.6O₃ Flexible Thin Films

Flexible electronics is a novel electronic technology that enables the production of electronic devices on flexible substrates.Compared to traditional electronic devices,flexible electronic devices offer superior flexibility,adaptability,and portability,and have vast application prospects in energy,display,storage,and other fields.In the case of flexible resistive switching memory devices,organic materials are widely used as the functional layer of the device due to their inherent flexibility.However,organic flexible devices often exhibit poor comprehensive performance.Conversely,inorganic ferroelectric thin films demonstrate higher electrical performance and superior chemical stability,which is critical for high-performance memory devices.Nevertheless,typical inorganic ferroelectric materials such as Pb（Zr,Ti）O₃（PZT）generally have limited strain capacity and cannot meet the requirements of flexible applications.Therefore,the study of all-inorganic flexible ferroelectric resistive switching memory devices is of significant importance.In this thesis,Au-PZT nanocomposite thin films were prepared on mica substrates using chemical solution deposition.The effect of the amount of Au on the resistive switching behavior of Mica/LNO/Au-PZT/Pt all-inorganic flexible resistive switching devices was studied.By analyzing the microstructure,ferroelectric properties,electrical conductivity,and flexibility of Au-PZT composite films with different Au molar fractions,the mechanism of the effects of Au composites on the electrical properties and flexibility of the device were elucidated.The main research results are as follows:Au-PZT ferroelectric nanocomposite thin films with Au molar fractions of 0.0%,1.0%,2.5%,5.0%,and 9.0%were prepared using chemical solution deposition.As the Au molar fraction increased,the ferroelectric properties initially increased and then decreased,and the ON/OFF ratio showed a similar trend.When the Au molar fraction was 2.5%,the device exhibited the best electrical performance,with a remnant polarization of 33μC/cm²and a ON/OFF ratio of 729,which was more than 70 times higher than that of pure PZT,and the conductivity increased by 1000 times.The analysis of the conduction mechanism showed that the improvement in the resistive switching performance of the device was due to the enhancement of the ferroelectric properties of the Au nanoparticles,as well as the more conductive pathways produced by the Au nanoparticles.All Mica/LNO/Au-PZT/Pt devices maintained excellent ferroelectric properties even when the bending radius was reduced to 2 mm.As the Au molar fraction increased,the flexibility of the device initially improved and then deteriorated.The best flexibility observed at an Au molar fraction of 5.0%.By comparing the surface SEM images and I-V curves of Mica/LNO/Au-PZT/Pt devices with different bending cycles and Au composite amounts,it was found that excessive Au nanoparticles in the composite would produce defects and holes in the film,deteriorating the microstructure,and thus excessive Au nanoparticles in the composite would affect the resistive switching behavior and flexibility.On the other hand,an appropriate amount of Au nanoparticles in the composite not only maintained the electrical properties of the inorganic ferroelectric thin film but also prevented the propagation of microcracks within the film,achieving synchronous improvement in electrical properties and flexibility.