Caractérisations Structurale, Optique et Electrique des Couches Minces du SnO2, Non Dopé et Dopé au Lithium, Elaborées par Spray Ultrasonique

Abstract

In this work, undoped and Li doped tin oxide thin films (SnO2 and Li: SnO2) were prepared by spray ultrasonic technique on ordinary heated, at 480 ° C, glass substrates during three minutes. The solution precursor was SnCl2 dissolved in methanol and for doping LiCl2 was added in the precursor solution. X-ray diffraction (XRD), UV-Visible spectroscopy and four point prop were employed to investigate the structural, optical and electrical characteristics of the films before and after doping. XRD showed that the films were tetragonal routile casteriste with (110) and (211) as preferred orientation for undoped and Li doped SnO2 respectively. Grain seizes were found to be in 29-33nm average. UV-Visible spectrum revealed that the prepared SnO2 films have transmittance value laying between 60-95% in visible region and optical gap varied between 3.72 to 3.87 eV for the undoped to 5.0%wt Li doped one respectively. Thin film thickness was estimated to be 200nm for the all samples. From electrical characterisation it was found that sheet resistance increases from 600 to 8.3x105Ω/cm2 after doping with 5.0%wt Li concentration which lead to an decrease in conductivity of the films