ITO films deposited on water-cooled flexible substrate by bias RF Magnetron Sputtering

Indium tin oxide ITO.films were deposited on water-cooled polypropylene adipate PPA.substrate using bias RF magnetron sputtering from a ceramic target composed of In2O3 90%.qSnO2 10%.. Good polycrystalline-structured ITO films with a low electrical resistivity of 6.3=10y4 V cm have been obtained by applying a negative bias of about y40 V to the substrate at a water-cooled substrate temperature 18"28C.. The visible transmittance of all obtained films was over 80% and in the wavelength range of 400–550 nm, the transmittances increase with increasing the negative bias. X-ray diffraction spectra revealed that all the films oriented preferably withw222xdirection andw400xdiffraction peak decreased with increasing the negative bias. Both the X-ray diffraction spectra and atomic force microscope AFM.measurement suggested that the average crystalline size, as well as the conductivity have a maximum value at the bias of about y40 V. The influences of argon pressure and the proportion of SnO2 on the conductivity of the films were also studied. The optimum argon pressure is 0.5–1 Pa, and the proper content of SnO2 is 7.5–10 wt.%. q2000 Elsevier Science B.V. All rights reserved.