  Thin films of Ti1-xCoxO2 (x=0 and 0.03) have been prepared on sapphire
substrates by spin-on technique starting from metalorganic precursors. When
heat treated in air at 550 and 700 C respectively, these films present pure
anatase and rutile structures as shown both by X-ray diffraction and Raman
spectroscopy. Optical absorption indicate a high degree of transparency in the
visible region. Such films show a very small magnetic moment at 300 K. However,
when the anatase and the rutile films are annealed in a vacuum of 1x10-5 Torr
at 500 oC and 600 oC respectively, the magnetic moment, at 300 K, is strongly
enhanced reaching 0.36 &#61549;B/Co for the anatase sample and 0.68
&#61549;B/Co for the rutile one. The ferromagnetic Curie temperature of these
samples is above 350 K.
