The Study On Preparation Of Oxide Electronic Ink And Its Thin-Film Transistor

With the rapid spread of mobile electronic devices such as smart phones,flat panel display technology has gained tremendous room for development.Thin-Film Transistor?TFT?technology has attracted wide attention as a common technology and core technology in flat panel displays.The mainstream TFT technology for flat panel display applications is amorphous silicon TFT,but due to its low mobility and poor stability,it is difficult to meet the demand for high resolution flat panel display?especially organic light emitting diode display,OLED?.Oxide TFTs have attracted the attention of domestic and foreign industry and academia due to their high mobility,uniformity and low preparation temperature.Currently,oxide TFTs prepared by a vacuum method have been applied to liquid crystal display?LCD?and OLED television products.Compared with TFTs prepared by vacuum method,solution-processed TFTs have the advantages of higher material utilization,lower production cost,and more suitable for large-area preparation.Solution processing TFT technology will be one of the development directions of TFT fabrication technology in the future.The work of this paper mainly studies the materials of solution processed oxide TFTs and the preparation of electronic inks and film preparation methods.The solution processing method is more dependent on the annealing temperature than the vacuum method.At present,most of the oxide precursor solution?ink?has a conversion temperature of 300°C or higher.Excellent ink formulations can meet both lower process temperatures and higher film quality requirements,so the preparation of oxide precursor solutions is a key technology in solution processing.For this technology,the first study of perchlorate in this paper,combined with the theoretical calculation of Gibbs free energy,in-depth study of the decomposition mechanism of perchlorate.On this basis,a nitrate-doped perchlorate oxide precursor ink formulation was further studied,which reduced the annealing temperature and improved the mobility.It has been found that when perchlorate and nitrate are present at the same time,the oxygen radical generated by nitrate will"attack"the perchlorate with a regular tetrahedral stable structure,causing the perchlorate to decompose at a lower temperature,while the high chlorine The decomposition of the acid radicals produces a large amount of oxygen and unstable intermediates,which further promotes the decomposition reaction,thereby lowering the annealing temperature.The TFT device based on nitrate-doped perchlorate oxide precursor ink has a mobility of up to 14.5cm²V^-1s^-11 at an annealing temperature of 250°C,and a mobility of more than 50 cm²V^-1s^-1 at an annealing temperature of 350°C.Not only the preparation temperature is lower than that of most solution processing oxide TFTs,but also the performance is superior.A new solution is proposed for the problem that the traditional nitrate precursor ink has a higher conversion temperature and the carrier concentration rises due to oxygen evolution under higher temperature annealing.Another low-temperature preparation method in the processing of oxide solutions has also been studied,namely film preparation based on oxide nanoparticle suspensions.Unlike the oxide precursor solution method,the oxide nanoparticles dispersed in the solution can be formed into a film without decomposition by the precursor.Therefore,the method for preparing the film does not require a high processing temperature and is compatible with most types of liners.The bottom film includes a flexible substrate having a decomposition temperature of less than 200°C and an elastic substrate.The effect of different dispersants?acetylacetone and PVP?on the film formation quality was also studied.An oxide TFT with a mobility exceeding 0.2cm²V^-1s^-1 was prepared at a low temperature of 150°C.Finally,a stretchable graphene electrode substrate was prepared,which laid the foundation for the preparation of the next stretchable device.