Microtexture analysis of copper-doped iron oxide thin films prepared by air pneumatic spray

The stereometric and fractal concepts are crucial tools to analyse, to verify, to report 3-D microtexture of thin film surfaces on the nanometre scale and thereby to generate useful topographic characteristics for better understanding and steering them toward further improvements and rational use in modern applications. At first, the present work aimed to prepare hematite α-Fe₂ O₃ thin films with (0, 2, 4, 6 and 8 wt%) of Cu doping by using the air pneumatic spray method. Subsequently, the obtained pure α-Fe₂ O₃ and Cu-doped α-Fe₂ O₃ thin films were characterised by XRD device, which determines their polycrystalline nature with the rhombohedral hematite structure. Analysis by UV-VIS absorption showed that the transmittance of the thin films is extinct in the wavelength from approximately 500 to 800 nm, revealing that the films have good optical absorbance in the visible region. The obtained bandgap values varied between 2.23 and 2.21 eV. At second stage, the stereometric and fractal analysis are applied on 3-D image data of pure α- Fe₂ O₃ and Cu-doped α-Fe₂ O₃ thin films, which in prior generated using AFM device. Accordingly, the obtained statistical parameters such as surface roughness, density distribution of peaks, depths etc. were used to understand the influence of Cu doping on the 3D microtexture of pure α- Fe₂ O₃ and Cu-doped α- Fe₂ O₃ thin film surfaces.