Study On Preparation Of Sr₂IrO₄ Based Electric Double Layer Transistor And Its Synaptic Behavior Simulation

In the recent years,5d transition metal oxides have attracted a great deal of attentions from worldwide researchers,especially its typical representative–iridates.Most of iridates possess a characteristic of special Mott insulator,which originates from the competition and balance of crystal field splitting,electron correlation effect and spin-orbit interaction.The complex origin of the electrical transport properties provides more possibilities for achieving a multi-state and nonvolatile resistive switching effect in iridates,and its electrical device realization has a great potential in next generation memory.Moreover,the multi-state and nonvolatile effect can meet the basic requirements of artificial synapse.Based on this,the device also has the potential applications on artificial synapse and neurocomputing.On the basis of the above significances,we fabricated Sr₂IrO₄ single crystal film on SrTiO₃ substrate by pulsed laser deposition.During the fabrication process,a method for selective growth of Ruddlesden-Popper Type strontium iridates was proposed.Then,we prepared special Sr₂IrO₄-based electric double layer transistors by conventional micromachining technology and did research on electric field control of the electronic properties of Sr₂IrO₄ thin films.The results showed a bidirectional resistive switching effect with an on-off ratio of over 1×10⁴.Based on this effect,we further studied the potential applications of the devices in the field of artificial synapse and some simulations of synaptic behaviors were demostrated,such as paired-pulse facilitation,potentiation/depression process and so on.This thesis is divided into five chapters:Chapter one is the foreword of this thesis,which introduces the background,significance and some related research progress.The emphasis is the introduction of Ruddlesden-Popper Type strontium iridates and electric double layer transistors.Meanwhile,we summarize the classification and properties of transition metal oxides.In chapter two,we describe the fabrication technology and characterization methods of films and devices.The contents from chapter three to chapter five are the experimental results of this thesis.In chapter three,we fabricated a series of Sr₂IrO₄ films with different thickness and explored the conditions for selective growth of different types of Ruddlesden-Popper Type strontium iridates from a single Sr₂IrO₄ target.In chapter four,we prepared electric double layer transistors and did the research on electric field control of the electronic properties of Sr₂IrO₄ films.And in the last chapter,on the basis of the results of chapter four,the simulation of a series of synaptic behaviors s were realized,demonstrating that these devices have potential applications in the field of artificial synapse.