43 巻 (2000) 8 号 p. 806-811
A simple evaporation technique have been proposed for the fabrication of all-solid-state electrochromic devices, and applied to high-temperature-oxidation of transition metals such as tungsten, manganese and tantalum. A wire coil of such a transition metal was heated by direct current flow in a vacuum chamber under less than 5.3 Pa, and metal oxide films were deposited on ITO glass substrates. The tungsten oxide films were found to be amorphous with slightly blue surfaces. The manganese oxide films showed less transparent, but the tantalum oxide films were transparent. Columnar morphology was observed for all these films. Electrochromic behavior of the as-deposited oxide films was examined with an applied voltage of 2V in 1M LiClO4 propylene carbonate electrolyte. It was confirmed that the tungsten oxide films show a cathodic type, and the manganese oxide films show an anodic type of electrochromic behavior. Technical points to be improved are summarized in terms of experimental results.