Couches minces de SnO2 nanocristallines obtenues par Sol-Gel et étude des conditions de leur cristallisation

Abstract

In this work we deposited thin layers SnO2 and of SnO2 doped to Indium 15% on the glass substrates by the dip-coating process and the sol-sol method. We applied the operation immersion-pulling up to seven times. The thicknesses of the layers are measured by ellipsometry, they lie between 130 nm and 185 nm. The samples annealings during 1h and 2h have lower thicknesses and indexes of refraction higher than those of the samples not annealings. When the time of annealing increases the thickness of the layers decreases and their indexes of refraction increase, this is directly related to the thickening of layers. On the other hand for the sample during 3h the thickness reheats increases and index of refraction decreases, this is related to the size of the grains. The spectra of diffraction of x-rays show an orthorhombic structure of these layers which they are doped or not doped. The structure is polycrystalline and the grains grow according to the <111>. Spectra SIMS show that the layers obtained are not clearly superimposed, the elements present in these layers are: 120Sn, 115In, more compounds: 120Sn16O, 120Sn16O2, and 115In16O. The distribution of these elements in-depth in a homogeneous general way in the case of the sample is not reheated. This distribution of the elements becomes important towards surface after annealing with 500°C. The spectra of transmission, in the field of average IR, of these layers show the vibrations of the groupings C-O, C–H, O-H, and also, of the vibrations Sn-O, Sn-O-Sn, Sn-OH. This wants to say that the organic matter, which enters the solution sol-gel, did not completely evaporate after the annealing of the layers with 500°C, which is during 2 h or 3h.