X-ray photoelectron spectroscopy investigation of ion beam sputtered indium tin oxide films as a function of oxygen pressure during deposition

Abstract

X-ray photoelectron spectroscopy analysis was performed on ion beam sputter deposited films of indium tin oxide as a function of O2 partial pressure during deposition. The oxygen partial pressure was varied over the range of 2.5×10−6–4.0×10−5 Torr. Changes in composition as well as in the deconvoluted In 3d5/2, Sn 3d5/2, and O 1s core level spectra were observed and correlated with the variation of the oxygen partial pressure during deposition. Results show that the films become increasingly stoichiometric as PO2 is increased and that the excess oxygen introduced during deposition is bound predominantly to the Sn and has little or no effect on the In–O bonding.