EFFECT OF PASSING ELECTRIC CURRENT ON THE ELECTRICAL AND OPTICAL PROPERTIES OF ITO FILMS IN AIR

The effect of passing electric current on the electrical and optical properties of indium tin oxide (ITO) films in air has been studied. Resistivities of the ITO films deposited by direct current magnetron sputtering on glass substrates were about 10.5 × 10-4Ωcm (group A) and 4.3 × 10-4Ωcm (group B). A constant electric current i between 30 and 150 mA was applied to the films in air for 3 h. The results show that there is a critical current (icri) for each group sample. icri of group A is 60 mA and icri of group B is 90 mA. When i > icri, the electrical performance declines and optical transmittance increases for the electric annealed sample. However, both the electrical and optical performances may be improved for the annealed film when i ≤ icri. It is found that the variations in electrical and optical properties of the films strongly depend on the electric power applied to ITO films.