Structural, optical and electrical properties of copper oxide thin films deposited by spray pyrolysis

Abstract

In this work, we have developed thin layers of CuO by method of pyrolysis spray. The samples developed are obtained from the use of copper chloride precursor CuCl2 with molarity of 0.1 mol/l and a spray number that varies between 25 to 150 spray with a step of 25 spray to see the effect of this parameter on the structural, optical and electrical properties of our material. The structural characterization of the obtained thin layers was done by X-ray diffraction (XDR) and spectroscopy Raman. The optical characterization was done by UV visible spectroscopy and electrical characterization by four points. The XDR has confirmed the crystalline state of our thin layers and the formation of the CuO with a preferential direction according to the plan (002). The Raman spectroscopy allowed us to confirm the presence of a thin layer based on the CuO. The lattice parameters remain mainly constant. The spectra UV visible of films has given a transmission varies between 80% and 40% in visible. The optical gap determined varies between 1.75 eV and 1.2 eV. Electrical characterization shows that the resistivity varied between 3.21KΩ.cm and 1.7KΩ.cm depending on number of spray for ethanol gas sensing applications.