Influences of sputtering power and substrate temperature on the propertiesof RF magnetron sputtered indium tin oxide thin films

Indium tin oxide thin films have been deposited on glass substrates using r f magnetron sputtering at different power densities (0.27-0.80W/cm(2))and a t different substrate temperatures (RT-250) degrees C. Film structure, crys tallite size. and orientation, optical absorption and bandgap have been stu died to characterize the films. Carrier concentration and Hall mobility hav e been determined by Hall effect. X-ray diffraction (XRD) analysis of room temperature (RT) deposited samples reveals a structural change from amorpho us to mixed amorphous/polycrystalline structure with [100] preferred orient ation with increasing rf power density The increase in substrate temperatur e results in a similar structural evolution from amorphous to a mixed phase followed, at temperatures higher than 200 degrees C, by a polycrystalline phase with [111] orientation. The study clearly indicates that ITO films do minated by oxygen vacancies prefer to grow with [100] oriented crystallites whereas the [111] oriented films are characterized by a more effective dop ing by tin.