Effect of plasma treatment on hydrophilic properties of TiO2 thin films

TiO2 films prepared by reactive sputtering technique were treated by Ar, O-2 and N-2 radio frequency plasma, respectively. The contact angles of water drop on the surface of TiO2 films, which were measured by drop shape analysis, decreased remarkably with plasma treatment for 1 min. With the increasing of plasma treatment time, the contact angles of the samples treated by O-2 plasma decreased rapidly to zero degree, while the contact angles of the samples treated by Ar and N-2 plasma decreased slowly. The improvement of hydrophilic property is due to the surface etching, ultraviolet radiation and surface oxidation of plasma treatment. (c) 2005 Elsevier B.V. All rights reserved.