In2O3:Sn (ITO) thin filmswith thickness of 200 nmwere grown on glass substrates by electron beamevaporation method at different deposition rates. The deposition rate was adjusted in the range between 3 nm/min and 12 nm/min. X-ray diffraction (XRD) analyses indicate that the ITO films are polycrystalline, having a bodycentered cubic (BCC) structure irrespective of their deposition rate. All ITO films showed preferred orientation along the (2 2 2) crystalline plane. The microstructural parameters such as grain size (D), lattice constant (a0), lattice strain (ε) and dislocation density (δ) were calculated. It is found that the deposition rate has an important role in controlling the microstructural parameters of ITO thin films. Surface morphology of the ITO thin filmswas studied using atomic force microscopy (AFM). The quantitative AFMcharacterization showed that the root mean square (RMS) surface roughness of the films decreases monotonically with increasing the deposition rate. The film deposited at lower growth rate has larger grains, and a larger grain size appears to correspond to a higher film surface roughness. Under optimized deposition conditions, an electrical resistivity of 3.04 × 10−4 Ωcm with RMS surface roughness of 4.41 nm was achieved for lower deposition rate 3 nm/min. Also, the film surface morphology does not directly affect the structural properties of the prepared ITO thin films.
