Preparation And Properties Of Nano-metal Films On Flexible PEN Substrates

Poly?ethylene 2,6-naphthalate??PEN?is a high-performance polyester material with good mechanical properties,thermal properties,air tightness and other properties compared with other polymer materials,acousto-optic carrier,electronic appliances,film and other fields is widely used,PEN film is also used in polymer earphone diaphragm materials.Compared with metal materials,PEN has the characteristics of light weight,good flexibility,non-conductivity,low elastic modulus and low rigidity.In recent years,with the development of flexible screens,smart wearable devices,solar cells,etc.,PEN is used as flexibility substrate composite materials are widely concerned and researched by developers and researchers.In order to solve the problems of low elastic modulus and low rigidity of PEN film,a layer of nano-metal film was deposited on the surface of flexible PEN film by DC magnetron sputtering.The aim was to obtain light weight,good flexibility,high modulus of elasticity and high hardness.A composite film material with good comprehensive properties.In this paper,PEN film and single crystal silicon wafer were used as th e substrate.The pure Ti target,Cu-Ti target and Cu-Be target were used to prepare nanostructured metal pure Ti film and Cu-Ti film and Cu-Be film under different sputtering powers.The effects of sputtering power on the microstructure and mechanical prop erties of Ti,Cu-Ti and Cu-Be films were investigated.The effect of sputtering power on the surface roughness of the coating,the adhesion of the metal coating to the PEN substrate,The anti-air oxidation properties of the nano-Ti film,the Cu-Ti film and the Cu-Be film prepared by controlled magnetic sputtering,and the adhesion of the Ti film,the Cu-Ti film and the Cu-Be film to the substrate PEN after oxidation.The results show that the titanium film deposited on the PEN flexible substrate by DC magnetron sputtering is a nano-polycrystalline film.With the increase of sputtering power,the deposition rate of titanium film and the elastic modulus of titanium film increase.The surface roughness of titanium film and the grain size of titanium film are both reduced;the increase of sputtering power will inhibit the columnar growth mode of titanium film;the process parameters when sputtering pressure is 7.0×10^-1 Pa and sputtering power is 144 W,the best performance composite film is obtained.The Cu-Ti film prepared by DC magnetron sputtering is a nano-metal film,in which Ti element is uniformly distributed in Cu-Ti mainly in the form of copper-titanium compounds Cu₄Ti₃ and Ti₂Cu₃.In the film,the grain size of Cu-Ti film increases with the increase of sputtering power;the roughness of Cu-Ti film increases first and then decreases,and the roughness is minimum when the sputtering power is 228 W;with the increase of sputtering power,The hardness of the film increases first and then decreases.When the sputtering power is 190 W,the hardness of the Cu-Ti film is the highest.When the working pressure is 0.7 Pa and the sputtering power is 228 W,the Cu-Ti film has the best synthesis performance.The Cu-Ti nanofilm contains a large amount of nano-metal Cu crystals,which is easily oxidized in the air,and the oxidation product is CuO,which deteriorates the film properties.In the Cu-Be film prepared by DC magnetron sputtering,Be element is mainly present in the film in the form of beryllium copper compound s Be₂Cu and BeCu.With the increase of sputtering power,the growth structure of Cu-Be film is improved,the loose tapered grain structure transforms into a dense fibrous structure;the sputtering power has little effect on the preferred orientation of the film.With the increase of sputtering power,the grain size of Cu-Be film increases,the hardness of the film increases first and then stabilizes,and the surface roughness of the film increases first and then decreases.When the sputtering power is 240 W,the roughness is minimum;when the working pressure is 0.7 Pa,the sputtering power is 240 W,the PEN/Cu-Be film prepared by magnetron sputtering has the best comprehensive performance and good film-substrate adhesion.The Cu-Be nano-film contains a large amount of nano-metal Cu crystals,which is easily oxidized in the air,and the oxidation product is CuO,which deteriorates the film properties.