Effect of deposition times of Al$_2$O$_3$ buffer layer on the structural and optical properties of AZO film on the polyethylene terephthalate substrates

摘要

The aluminium-doped zinc oxide with Al$_2$O$_3$ buffer layer (AZO/Al$_2$O$_3$) films were deposited on the polyethyleneterephthalate substrates by radiofrequency magnetron sputtering. Compared with the AZO films without Al2O3 buffer layer, the crystallite size and (002) peak of the AZO/Al$_2$O$_3$ films changed with the deposition times; the full-width at halfmaximum (FWHM) of (002) peak decreases from 0 to 25 min. The effects of Al2O3 buffer layer on the surface morphology of AZO/Al$_2$O$_3$ and optical properties of films were investigated by SEM and UVa??Visa??NIR spectrophotometer, respectively. The results reveal that the average transmittance of the AZO films in the visible wavelength region is $sim$90%, stronger deep level emissions centred on 550 nm is attributed to intrinsic defects in the AZO films on the organic polymer PET substrates.