Preparation of the CrO 2 thin films using a Cr 8 O 21 precursor

We have prepared a CrO 2 thin film by chemical vapor deposition from a Cr 8 O 21 precursor and studied the bulk and surface physical properties. The CrO 2 thin film is grown on TiO 2 (100) substrate by heating precursor and TiO 2 (100) substrate together in a sealed quartz tube. The prepared film is found from x-ray diffraction analysis to be an (100)-oriented single phase. The magnetization and resistivity measurements indicate that the film is a ferromagnetic metal with a Curie temperature of about 400 K. Cr 3 s core-level and valence band photoelectron spectroscopy spectra reveal the presence of a metallic CrO 2 in the surface region of the film. Our work indicates that preparation from a Cr 8 O 21 precursor in a closed system is promising for obtaining a CrO 2 thin film with the metallic surface.