Improvement of Tin Oxide Structural Properties under Annealing Treatment
Tin oxide thin films were deposited by spray pyrolysis technique on glass substrate at Td=350°C during 30 min
using SnCl2-2H2O precursor. The surface structural characteristics and morphological properties have been studied by XRay
Diffraction (XRD), Scanning Electron Microscopy (SEM), Energy dispersive X-ray Spectroscopy (EDX), and Atomic
Force Microscopy (AFM). From XRD patterns, we can see the presence of SnO and SnO2 peaks for the as-deposited film,
while after heat treatment (Ta=450°C, 1h) the structure changed to form pure SnO2phase. SEM revealed for the as-deposited
film a polycrystalline surface with sand rose shape agglomerates formed by sheets estimated between 0.2 μm - 1.5 μm. After
annealing, the film surface changed to form round agglomerates with a size varying from 0.5 μm to 2.5 μm. EDX analysis
confirmed the formation of SnO and SnO2 for the as-deposited film and the annealed one respectively. Root Mean Squared
high (RMS) obtained from AFM decreased from 422 nm to 256 nm after annealing. Consequently, all results are well
correlated and confirm the improvement of the structure and morphology of deposited tin oxide films afterheat treatment.
Keywords - Tin Oxide Thin Films, Spray Pyrolysis, Annealing, XRD, SEM, EDX, AFM.