CVD-TRANSITION METAL OXIDE FILMS AS FUNCTIONAL LAYERS IN 'SMART WINDOWS' AND X-RAY MIRRORS

摘要

The properties of transition metal oxides are mainly determined by their specific band structure and electron distribution. Electrically activated materials are very interesting due to the variety of potential applications, including elements for information displays, antiglare rearview mirrors, sunroofs and smart windows. CVD-preparation, structure and optical properties of Mo and W based oxide films are presented. The color efficiency of electrochromic (EC) devices with a Mo/W mixed oxide film as working electrode is over 100 mC/cm~2, and the optical modulation above 50% at 550 nm. WO_3 and MoO_3 films in double layers with SiO_2 films with thickness of a few nanometers form optical systems, i.e. X-ray mirrors. By PECVD technology, mirrors of 24 periods of 5 nm thick MoO_3/SiO_2 double layers were forming such an optical system. Based on diffraction in such an "artificial crystal" optical system, an increased reflection is obtained in the "water window" wavelength region, where all materials are highly absorptive. The reflected beam with wavelengths in this region could have a number of practical applications.