Effects of processing parameters on crystalline structure and optoelectronic behavior of DC sputtered ITO thin film

摘要

DC magnetron sputtering technique has been used to deposit highly transparent and conducting films of tin-doped indium oxide (ITO) onto externally unheated glass substrate, with and without annealing. The ITO thin films were obtained by varying the working pressure and the DC power as critical process parameters. The effects of variation of the deposition parameters on the deposition rate, microstructural, electrical, and optical properties have been investigated in this paper to study electro-optical characteristics of ITO films. The microstructural, electrical and optical properties of the sputtered ITO films were systematically characterized by X-ray diffraction, atomic force microscopy, four probe electrical conductivity and optical spectroscopy. A minimum sheet resistance 16 Ω/ square and transmittance 85 % with a Haacke's figure of merit 12 × 10~(-3) Ω~(-1) thickness of 230 nm and optical band gap 4.09 eV are obtained for the thin films grown on externally unheated substrate at 100 W DC power and 32 mTorr working pressure.