Size-dependent structural, electrical and optical properties of nanostructured iron selenide thin films deposited by Chemical Bath Deposition Method

FeSe thin films of thickness 60-273 nm were prepared by Chemical Bath Deposition (CBD) method at room temperature by using Fe(NO3)(3).9H(2)O and Na2SeSO3 as cationic and anionic precursor with EDTA as a complexing agent. For structural characterization X-ray diffraction and FTIR techniques were used. The morphological characterization of FeSe thin films were carried by using scanning electron and atomic force microscopy. The compositional analysis of FeSe thin film was carried by using EDX setup attached with scanning electron microscope. The semiconducting behavior of FeSe thin films has been studied by using two-probe method of electrical resistivity. The resistivity at 373 K temperature decreases from 46 x 10(4) to 2 x 10(4) Omega-cm as thickness increases from 60 to 358 nm. FeSe films have direct band-gap that changes from 2.74 to 2.55 eV depending on crystallite size which supports Quantum Size Effect. (c) 2012 Elsevier Masson SAS. All rights reserved.