Properties Of Thin Film Deposited By Spatial Atomic Layer Deposition On Organic Substrates And Expansion Design Of Equipment For Flexible Display Field

Flexible display is an emerging science and technology with a broad market prospect.However,as products continue to be updated iteratively,the quality requirements for thin-film functional layers will become more and more important,and it is necessary to find thin-film deposition technologies that can achieve large areas,high quality and be compatible with flexible manufacturing.Spatial Atomic Layer Deposition(S-ALD),a kind of Atomic Layer Deposition(ALD),trades space for time and can rapidly prepare films while retaining the advantages of ALD technology such as high aspect ratio,large area uniformity and nanoscale thickness control.However,the development of S-ALD technology started late,and now it still faces two problems: the influence of stresses in production and use on film properties is unknown,and the small size of production equipment is difficult to keep up with the needs of large area uniform film deposition.This paper conducts in-depth research on the two problems and makes the design scheme that can solve the problem.The work mainly reflects the following aspects:(1)To study the film properties of the flexible organic substrate deposited under strain.The optical and tensile properties of the film were researched by using ellipsometer,step instrument,3D microscope and other characterization instruments,and the law of film properties under strain was obtained.Combined with theoretical calculations,the critical radius of curvature that the film can withstand is obtained,and the pre-strain pull-down performance is improved up to 213%;the simulation analysis of the changes in optical properties shows that the total transmittance decreases 0.5% under pre-strain.(2)The advantages and disadvantages of domestic and foreign S-ALD equipment were analyzed.Based on the existing equipment,an expanded design scheme combining dual working conditions and modularization was proposed,and engineering problems such as sealing and heating uniformity were solved.Coupling the fluid model,heat transfer model,structural statics and chemical reaction model of the thin film deposition process in the modular design process,and using simulation calculation to guide the structural design optimization.The injector module optimizes the size of the internal flow channel and adds side flow channels to improve the uniformity of the distribution of the precursor gas flow on the substrate.The heating module simulates and optimizes parameters such as the reserved gap of the heating plate,the size of the substrate base,and the height of the micro gap band,and finally obtains the optimal solution of the structural parameters.The process parameters of different working conditions were optimized,and the best process plan was obtained,which greatly improved the performance.