The Study Of Flexible Electronic Device Based On Bi_3.25La_0.75Ti₃O₁₂and CsPbBr₃ Film

With the gradual rise of wearable devices,flexible electronic devices have become the future development direction of electronic devices.The ABX₃ perovskite materials occupy a very important position or show strong application potentials in many fields.We summarized the flexible devices preparation methods into 6 different methods,of which we mainly used two methods:directly preparing electronic devices on organic flexible substrates and preparing electronic devices on hard mica substrates and then reducing the mica substrates to access the flexibility.In this paper,we study two famous inorganic perovskite materials:Bi_3.25La_0.75Ti₃O₁₂and CsPbBr₃.Bi_3.25La_0.75Ti₃O₁₂ has the advantages of high remanent polarization and low working voltage,which can meet the performance requirements of ferroelectric memory,and itself is a semi-transparent material.By choosing the appropriate substrate and electrode materials,we finally produced the prototype device of flexible and transparent ferroelectric memory with the structure of Mica/Ag-ITO/BLT/ITO.The device has an overall light transmittance of 70%-80%in the visible band,and can withstand more than 10000 bending times with a radius of 2.2 mm.In the continuous reading and writing test,the upper electrode was scorched due to excessive heat after about 10⁷ cycles.However,this problem can be avoided when the rest time is inserted to assist heat dissipation in the test.We also studied the information retention life of the device and found that the device is expected to retain data for more than 10 years in case of power failure.CsPbBr₃ has the advantages of high carrier mobility and quantum efficiency.It has a bright application prospect in the field of luminescence and photoelectric detection.We prepared CsPbBr₃ films with[100]orientation by spin coating and pulsed laser deposition,and designed a flexible PI/Au/CsPbBr₃/Au optical detector prototype device based on it.Since the components can be regarded as single crystals in a very small area,the problem of small response due to high trap state density of common CsPbBr₃film is avoided.Because the thin film is only a few hundred nanometers thick,the slow response speed of the large-sized single-crystal CsPbBr₃ photodetector is avoided.The PI/Au/CsPbBr₃/Au optical detector prototype device has a switching ratio of up to 10⁶,and has the advantage of working normally without applied bias voltage.The detection range is large and can detect extremely weak light of 1?W/cm² and respond in less than 0.5 ms.We have also tested its photoelectric properties under bending conditions and found that it has excellent flexibility.In conclusion,we researched on the preparation methods of perovskite thin film flexible electronic devices,selected Bi_3.25La_0.75Ti₃O₁₂ to prepare flexible and transparent ferroelectric memory prototype devices,and used CsPbBr₃ to prepare flexible optical detector prototype devices.It has made a certain contribution to the application of perovskite film in the field of flexible electronic devices.