E. Pedrero

Structural analysis of TiO2 films grown using microwave-activated chemical bath deposition

Abstract TiO2 layer films were grown using the microwave (MW)-activated chemical bath deposition technique on two different indium tin oxide substrates. The TiO2 films are studied to determine their structural response when changing the MW heating power. Thickness (areal density), oxygen concentration profile, composition and surface homogeneity were determined using Rutherford backscattering spectrometry, nuclear reaction analysis and atomic force microscopy. The analysis showed that the composition, thickness and surface structure of the films are highly influenced by MW heating power. The substrate, acting as seed for nucleation, influences the layer thickness, indicating that a thinner layer of TiO2 is obtained for the more conducting substrates. The oxygen concentration profile is constant in the TiO2 layer at low MW heating, power (≈20%). The rugosity of the samples and the non-homogeneity increase with the MW heating power. If the MW heating power is high enough pinholes in the TiO2 layer of the order of the sample thickness are produced.

Rutherford backscattering spectrometry analysis of TiO2 thin films

Abstract TiO 2 layers grown by microwave-activated chemical bath deposition (MW) and dip coating (DC), as well as by the combination of both techniques, were studied by Rutherford backscattering spectrometry (RBS), atomic force microscopy (AFM) and scanning electron microscopy (SEM). RBS analysis allows the determination of the stoichiometry and the thickness (in atoms/cm 2 ) of the TiO 2 layers. TiO 2 layers grown by DC have higher growth rates on a TiO 2 film obtained by MW compared to deposition directly onto an indium–tin oxide (ITO) substrate. TiO 2 layers grown by MW on a film obtained by DC have higher growth rates when compared to layers deposited onto ITO substrates. In this case, AFM analysis shows that the surface is rough and RBS reveals the presence of holes in TiO 2 films.