دراسة الخصائص الفيزيائية للطبقات الرقيقة لأكسيد الزنك(ZnO) مطعمة بـ (La) مرسبة بتقنية الرش الكيميائي الحراري

Abstract

Zinc oxide (ZnO) is a Transparent Conductive Oxide TCO material with interesting physical properties, which places it among the most promising materials for use in various fields such as piezoelectricity, photovoltaic effect, optoelectronics...etc. In this work, we have prepared, undoped and La doped ZnO thin films, with flowing concentrations: by percentage wt = 0, 1, 2, 3 and 5. La was used as source of dopant in the precursor of Zn which wasobtained by dissolving zinc acetate in 1:1 methanol-double distilled water a concentration of (0.5 M) on glass substrates. During deposition by spray pyrolysis technique in VTRS laboratory at El-ouad University,glasssubstrates were kept out at 375 °C. A fundamental study of their structural and optical properties such as crystallization, optical transmittance spectra,energy gap and grain size of these materials were realized using XRD, Vis.UV and FTIR .X-ray diffraction analysis showed that all the films are polycrystalline with a hexagonal wurtzite structure with(002) preferred orientate of films ( wt%=0, 1, 3). and increased grain size increase vaccination Spectrophotometric measurements in Vis. UV range have showed that all the films have a high transmission of the extent of wavelengths (300-900 nm) about 85% in the visible zone with a band gap energy ranged in (3.28 -3.21) eV.It was found that the disorder of defects in the structure surveyed by deducting the Urbuch energy did not affect the energy band gap, ranged in ( 56.05 (86.98 meV. FTIR measurements showed Zn-O vibration bands at 400 to 700 Cm-1range. The addition in doping concentration leads to light deviation of bands.