Structural and morphological properties of ITO thin films grown by magnetron sputtering

Physical properties of transparent and conductingindium tin oxide (ITO) thin films grown byradiofrequency (RF) magnetron sputtering are studiedsystematically by changing deposition time. The X-raydiffraction (XRD) data indicate polycrystalline thin filmswith grain orientations predominantly along the (2 2 2) and(4 0 0) directions. From atomic force microscopy (AFM) itis found that by increasing the deposition time, theroughness of the film increases. Scanning electron microscopy(SEM) images show a network of a high-porosityinterconnected nanoparticles, which approximately have apore size ranging between 20 and 30 nm. Optical measurementssuggest an average transmission of 80 % for theITO films. Sheet resistances are investigated using fourpointprobes, which imply that by increasing the filmthickness the resistivities of the films decrease to2.43 x 10(-5) Ω cm.