Preparation And Application Of AZO/Ag/AZO Flexible Transparent Electrode On Mica

Transparent conductive films are widely used in liquid crystal displays,solar cells,and LEDs due to their low resistivity and high transmit tance.Currently,ITO is the most widely used commercially,but In and Sn are rare metals,resources are scarce,Therefore,we must look for alternatives to ITO films.AZO is the best alternative to ITO,but it is brittle and has no flexibility,which cannot satisfy the use and development of flexible electronic devices.However,inserting a thin layer of A g in AZO can solve this problem,and significantly improve the conductivity of the film.The commonly used substrates for growing such flexible transparent conductive films are mainly pol ymer substrates,which have good flexibility,but they are not resistant to high temperatures and are susceptible to aging.However,mica has these two excellent properties,it has the advantages of flexibility,high temperature resistance up to 1000°C,and good light transmission,so it is an excellent flexible transparent substrate.In this paper,AZO/Ag/AZO multilayer transparent conductive fi lms were deposited on the mica substrate by magnetron sputtering.The effects of the thickness of Ag layer on the structure and properties of multilayer transparent conductive films were studied.The flexibility and high temperature resistance of Mica/AZO/Ag/AZO multilayer films were studied.Finally,they were used as electrodes in the full transparent flexible field effect transistors.The specific findings are as follows:?1?In the study of the effect of Ag inserting layer thickness on the optical and electrical properties of Mica/AZO/Ag/AZO films,the resistivity decreases monotonically with the increasing of Ag layer thickness,and the transmittance first decreases,then increases,and finally decreases again.Multilayer films with8 nm's Ag inner layer show the highest FOM value of 30.2×10^-3?^-1,due to low resistivity of 3.5×10^-5?cm,and high optical transmittance of 83.1%in the visible light range?400-800 nm?.And,AZO/Ag?8 nm?/AZO multilayer films grown on mica possess a superior flexibility.?2?Mica/AZO/Ag/AZO multilayer films with an 8 nm's Ag layer was annealed in vacuum for 30 min in the temperature range from 250 to 750?.It was found that the heat treatment temperature had no significant effect on the transmittance of the film,and the film resistivity remained stable at 550°C.Even after high temperature annealing up to 750?,The properties of Mica/AZO/Ag/AZO multilayer films also meets the practical use as transparent electrodes.?3?Using Mica/AZO/Ag?8 nm?/AZO as the gate el ectrode,Al₂O₃ and Zn O as the dielectric layer and the semiconductor layer respectively,and AZO as the source and drain electrodes,a fully transparent and flexible field effect transistor was fabricated,but no fi eld effect was found.