Surface physical property of the CrO 2 thin films prepared using a closed chemical vapor deposition method

We have examined the intrinsic surface physical property of a CrO2 thin film by means of surface sensitive photoemission spectroscopy. Epitaxial thin film of CrO2(100) has been grown on TiO2(100) by a closed chemical vapor deposition method using a Cr8O21 precursor. Low-energy electron diffraction (LEED) observations find that epitaxial growth of rutile-phase CrO2 occurs to the top monolayer of the film. Surface sensitive x-ray photoemission spectroscopy (XPS) measurements show a finite intensity in the region of the Fermi energy. The result evidences that the physical nature of near topmost layer of CrO2 thin film is metallic. Progress of understanding of the surface physical property of CrO2 thin film helps not only perform a reliable photoemission study to understand the physics of ferromagnetic metal in CrO2, but also develop the CrO2-based devices using a half-metallic nature for spintronics applications.