陽極酸化Ta₂O₅薄膜の電気的特性

The dielectric constant, the dielectric　loss, the breakdown voltage and the current at high electric fields of Ta₂O₅ 1ayers have been measured using Ta-Ta₂O₅-Au devices with various thicknesses. The Ta₂O₅ layer is prepared by anodizing sputtered Ta films. The rate of anodic oxidation is about 16-18Å/V. The Ta-Ta₂O₅-Au devices with the Ta₂O₅ layers more than 1500Å thick are electrically stable and show the dielectric constants of 20-25, which are slightly smaIIer than those of bulk (25-27). The current at high electric fields depends strongly upon temperature and therefore is considered to be the Schottky current. The breakdown electric field is about 5x10⁶V/cm. A few of the Ta-Ta₂O₅-Au devices studied show the remarkable rectifying characteristics, which may be due to the n― i―p junction of the Ta₂O₅ 1ayer.