Contribution to carrier densities of the oxygen vacancy in a low-resistivity tin-doped indium oxide film by the hot-cathode plasma sputtering method

In order to clarify the contribution to carrier density by oxygen vacancies in tin-doped indium oxide (ITO) films prepared on glass substrates by the hot-cathode plasma sputtering method, we have investigated the effect of annealing on the electrical properties of an ITO film with a resistivity of 1.0 x 10(-4) Omega cm. A drastic decrease in carrier density from 2.0 x 10(21) to 0.88 x 10(21) cm(-3) was found with gradual increase in the Hall mobility from 29 to 35 cm(2) V-1 s(-1) for repeated annealing cycles, when the ITO film was exposed for one hour to 400 degrees C oxygen gas at atmospheric pressure. The results indicate that the contribution of oxygen vacancies to carrier density was ca. 1.12 x 10(21) cm(-3) for the ITO film with an overall carrier density of 2.0 x 10(21) cm(-3). (C) 2009 Elsevier B.V. All rights reserved.