In the present work, we investigate the structural and optical properties of Zn x-1 Mg x O composites prepared by the standard sintering method at 1200?C during 24 hours and doped with different percentages of magnesium x between 0% and 40%. For this purpose, we have used the X-ray diffraction (XRD) and the atomic force microscopy (AFM) to study the effect of the magnesium’s proportion on the crystalline and morphology proprieties of the obtained samples. XRD analysis showed that all films are polycrystalline with a hexagonal wurtzite structure, with an orientation of the grains according to directions (0002) and (10-10). The AFM characterisation show that the degree of surface roughness (RMS) increases with the increasing of MgO content. Optical properties of the ceramics were investigated by Absorbance and Reflectance measurements at room temperature in the wavelength range 200 - 2400 nm. Optical band gap energies (Eg) were determined. Further cathodoluminescence and dielectric measurements would be carried out to study the influence of MgO doping on the dielectric and luminescent properties of the ZnMgO ceramics.
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