STUDY OF THE EFFECT OF THE OXYGEN PARTIAL-PRESSURE ON THE PROPERTIES OF RF REACTIVE MAGNETRON-SPUTTERED TIN-DOPED INDIUM OXIDE-FILMS

The influence of the oxygen partial pressure on the properties of indi um tin oxide films deposited by rf reactive magnetron sputtering has b een studied. The oxygen partial pressure was varied from 3.2 x 10(-4) to 1.0 x 10(-3) mbar. It has been found that the 4 x 10(-4) mbar of ox ygen partial pressure is a critical point. When the oxygen partial pre ssure is lower than 4 x 10(-4) mbar, the deposition rate of the films is high; the films have low transmittance and electrical resistivity; the X-ray diffraction shows that the films have a random orientation a nd the images of the scanning electron microscopy show that the films surface are smooth without structure. When the pressure is higher than 4 x 10(-4) mbar, the deposition rate is low and does not change as th e oxygen partial pressure is further increased; the transmittance and the electrical resistivity are both high; the films show the preferred orientation along the (440) direction; the films surface show a clear structure and as the pressure is increased further, the films become porous. Considering both the factor of transmittance and resistivity, the optimum oxygen partial pressure will be 3.6 x 10(-4) mbar. The fil ms prepared at this pressure have 80% transmittance and 9 x 10(-4) Ome ga cm resistivity. (C) 1997 Elsevier Science B.V.