Transparent Conductive Cu Films And WO₃/Cu/WO₃ Composite Films Prepared By Magnetron Sputtering

In the field of transparent condutive materials,due to the advantages of simple structure,good mechanical flexibility,excellent and stable optoelectronic properties,and convenience for large-scale production,three-layer films of oxide-metal-oxide structure have gradually become an alternative of indium tin oxide?ITO?films.Studies have shown that the intermediate metal layer plays a leading role in the photoelectric properties of the three-layer film.Therefore,in this paper,a series of single-layer Cu films with different thicknesses were first prepared by RF madnetron sputtering under three deposition conditions?sputtering power of 34 W and sputtering atmosphere of Ar,sputtering power of 136 W and sputtering atmosphere of Ar and sputtering power of 34W and sputtering atmosphere of Ar+H₂?.The effects of the introduction of H₂ into deposition atmosphere and sputtering power on the crystallinity,surface morphology,transparent conductivitve properties,and aging stability in the air of the Cu film were systematically investigated.Then,the effects of the N₂ atmosphere on the structure and photoelectric properties of the Cu film were also studied.Finally,based on the investigation of a single-layer Cu film,a WO₃ layer was deposited using a pulse magnetron sputtering method,and the WO₃/Cu/WO₃ three-layer films were prepared when the deposition conditions of the WO₃ layer were unchanged.The effect of the deposition conditions of Cu layer on the photoelectric properties of the three-layer film was investigated.The main results obtained are as follows:?1?When Cu film is deposited in pure Ar atmosphere,the increase of sputtering power can increase the deposition rate and crystallinity of the Cu film,reduce the surface roughness of the Cu film,enhance the conductive properties and transparency of the film,and improve the stability of the film in air.When Cu film is deposited at the same sputtering power,the introduction of H₂ into the sputtering atmosphere can improve the crystallinity more significantly and also enhance the photoelectric properties of the Cu films.However,it reduces the deposition rate,significantly increases the surface roughness and debases conductive stability in air of the Cu film.?2?The introduction of the N₂ atmosphere increases the surface roughness of the ultra-thin Cu film,improves the conductivity of the film when its thickness is less than8 nm,and reduces its optical transmittance.Taken together,the introduction of N₂ in the deposition atmosphere does not improve the photoelectric properties of the Cu film.?3?Silimar with single Cu films deposited on glass substrate,increasing sputtering power?from 34 to 136 W?of Cu layer can also obviously decrease the surface roughness of Cu films deposited on WO₃ films.Furthermore,the photoelectric properties of WO₃/Cu/WO₃ three-layer film can be obviously improved by increasing sputtering power of Cu layer.When the Cu layer is deposited at sputtering power of 136 and 34 W,the maximum figure of merit?FOM?of 7.79×10^-3 and 2.67×10^-3?^-1 are achieved for the WO₃/Cu/WO₃ three-layer film at the Cu layer thicknesses of 9 and 12 nm,repectively.?4?When the Cu layer is deposited at lower sputtering power?34 W?,the introduction of H₂ into deposition atmosphere increases the surface roughness of the Cu films deposited on WO₃ films and significantly improves the photoelectric properties of the WO₃/Cu/WO₃ three-layer film,which is consistent with the effect of the introduction of H₂ on the surface roughness and photoelectric properties of single-layer Cu films.At the Cu layer thickness of 11 nm,the WO₃/Cu/WO₃ three-layer film has the best photoelectric properties,namely,its FOM can be achieved with 1.07×10^-2?^-1.When the Cu layer is deposited under high sputtering power?136 W?,the introduction of H₂into deposition atmosphere cannot improve the photoelectric properties of the WO₃/Cu/WO₃ three-layer film.