Research On Electrofluid Lithography Manufacturing Process Of Ultra-Wideband Transparent Conformal Antenna

Ultra-wideband transparent conformal antennas have the advantages of light weight,high integration,and miniaturization.They have a very broad development space in the fields of military,aerospace,and civil 5G antennas.The transparent grid conductive film can be used as an antenna radiation unit and has good comprehensive optoelectronic properties.However,most of the current manufacturing processes of grid films are based on planar structure,with low manufacturing accuracy and high cost.In this paper,an ultrawideband antenna structure is designed,and a grid film that can be used for transparent radiation units is fabricated by electrofluidic lithography.The grid film is patterned and printed twice on a flat,curved,and flexible substrate to obtain an ultra-wideband Transparent antenna structure.The performance of the antenna was tested,which proved the rationality and effectiveness of the transparent grid antenna made by the electro-fluidic lithography process.The main work of this paper includes:A small ultra-wideband antenna structure was designed,and the optimized design of the antenna structure was completed using CST simulation software,and a film antenna structure with a working frequency band covering 3.1 to 10.6 GHz was obtained.The factors affecting the work performance are analyzed,such as the transparent grid treatment of the radiation unit and the conductivity of the film.The feasibility of the transparent grid antenna is proved.When the square resistance of the film is increased from 1Ω/sq to 20Ω/sq,the antenna pattern is basically unchanged,but the radiation efficiency is reduced from 85.9%to 20.5%.It is concluded that in order to improve the antenna The work performance needs to improve the conductivity of the transparent radiation unit.Design theoretical formulas based on the performance parameters of the grid film,and obtain the transmittance,conductivity and comprehensive quality factor corresponding to the radiation unit films of different sizes and structures.The electrofluid lithography process is used to fabricate the antenna transparent radiating element grid film on the plane and curved surface structure.The influence of the process parameters on the printing line width is studied.The performance test proves that the fabricated film structure has good adhesion,and After heat treatment,the square resistance of the film can be further reduced.When the light transmittance of the fabricated mesh film is greater than 85%,the square resistance can reach 6Ω/sq.In order to further improve the overall performance of the film,an ITO/Cu grid composite film was fabricated,and three fabrication methods of high aspect ratio grid films are proposed and experimentally explored.The ultra-wideband transparent antennas were successfully fabricated on flat,curved,and flexible substrates.The basic performance of a grid antenna with a light transmittance greater than 85%was tested and compared with the performance of an ordinary solid film antenna.Through the comparison of the actual measurement and the simulation results,it is proved that the better the conductivity of the mesh film is,the better the impedance matching performance of the antenna is,and the measured pattern of various transparent antenna structures are consistent with the simulation results,meets the design requirements.