ZnTPP-Based Memristors For Neuromorphic Application

Human brain is a highly parallel information processing system,whose efficiency is unmatched by traditional electronic devices.Inspired by the efficiency of the brain,memristors meets potential requirements for neuromorphological information storage and processing and has received more and more research and attention.However,so far,memristors have only made great progress in the inorganic field,and organic memristors have not yet obtained in-depth research results.But,organic memristors have a promising application prospect due to their simple film formation,low cost,and flexible stretchability.At present,the successful preparation of organic memristors and their own stable repeatability still face severe challenges.Therefore,the design and preparation of highperformance organic memristors have significant research significance in the field of neural function simulation.In this paper,based on ionic memristors,a series of Zn TPP-based organic diode memristors are designed and fabricated.The mechanism,performance and applications of the synaptic function simulation are deeply studied,which promotes the theoretical development and practical application of organic memristors.(1)The carriers in the traditional memristor have uncontrollable and random characteristics along the grain boundary,so the resistive characteristic curve is rough and unstable.Compared to inorganic memristors,organic memristor memristors based on Zn TPP can precisely regulate the transport of carriers through the formation and fracture of coordination bonds formed between the central metal zinc ions and oxygen ions,thereby achieving a stable,smooth and gradual resistive behavior.We have obtained three different properties of organic memristors by adjusting the thickness of different Zn TPP,and found that the dependence on the thickness of the active layer porphyrin zinc thickness,which lays the foundation for the construction of a multi-functional memristive device group.(2)In view of the fact that the porphyrin zinc organic memristor prepared by magnetic sputter evaporation has a stable,smooth,gradual resistance behavior,a solution processing method is used to prepare the memristor.The memristor prepared by solution processing is easier to realize largearea preparation,has a higher yield,still realizes the basic features of the memristor,and can perform simulations of bio-synaptic potentiation or depression and learning behaviors.The solution processing mentioned here is based on the ITO glass substrate,because the zinc porphyrin is not easy to film when spin-coated to the flexible PET-ITO interface,which is the most important point to be improved in the later stage.(3)Exploring the use of porphyrin zinc organic memristor for flexible substrates in order to obtain flexible memristors that are more suitable for practical applications.In this study,a powerful and flexible simple synaptic device based on the Zn TPP memristor achieves several biological synaptic functions similar to the human brain system.It uses oxygen vacancies,which is one of the key species to implement the memristor switching mechanism and can be used as an electronic coupling carrier for organic flexible memristors.Mixed ion and electron conduction mechanisms are effective tools for simulating biological synapses and achieving partial brain functions.In addition,the performance of organic memristors with different bending times and bending radius are mainly studied synaptic.The robustness of the results shows the possibility of designing flexible memristors using organic materials,and most importantly,this will accelerate the implementation of wearable smart computers.