Metal organic precursor effect on the properties of SnO2 thin films deposited by MOCVD technique for electrochemical applications

Abstract

Tin dioxide (SnO2) thin films are deposited by metal organic chemical vapor deposition (MOCVD) on Si substrates from three commercial metal organic precursors. The morphology and the microstructure of the films are observed by field emission gun-scanning electron microscopy (FEG-SEM). The films are dense and made of crystallites with a nanometer size. The structural properties of the films are assessed by grazing incidence X-ray diffraction (GIXRD). A tetragonal SnO2 phase is observed in the deposited thin films with various texturations as a function of the metal organic precursor used for the deposition. Chemical characterizations of the thin films are also carried out by Fourier transformed infrared spectroscopy (FT-IR) and by X-ray photoelectron spectroscopy (XPS). Finally, the observed morphological, chemical and structural modifications induce changes in the electrical properties of the film. Results are discussed and indicate that the electrical properties of the synthesized SnO2 thin films differ as a function of the MOCVD precursor used for the deposition. Therefore, their electrochemical behavior is modified which influences the grafting of organic molecules to synthesize and develop novel hybrid materials sensors.