Accession Number:

ADA453593

Title:

Electrolytic Preparation of High Dielectric Thin Films

Descriptive Note:

Contract rept.

Corporate Author:

LOCKHEED MISSILES AND SPACE CO INC PALO ALTO CA

Personal Author(s):

Report Date:

1966-01-01

Pagination or Media Count:

57.0

Abstract:

Several approaches toward the formation of high dielectric materials in thin film form by electrolytic techniques are considered, with emphasis on barium titanate. Some attention is devoted to zirconates, niobates, and tantalates. In addition to barium compounds, the comparable calcium, magnesium, strontium and potassium double oxides are evaluated by the appropriate electrolytic techniques. Rare earth double oxides are also considered, but dielectric properties are considered to be too marginal for inclusion in this study. The basic technique employed is anodization of the applicable refractory metal with a simultaneous deposition or occlusion of the second oxide in the anodized film. Experiments are described applying this basic technique to aqueous electrolyte systems, organic electrolytes and gas phase systems. Molten salt systems were eliminated on the basis of excessive solubility of product oxide materials. Films produced were evaluated in terms of pertinent capacitive and resistive properties. X-ray diffraction and spectrographic analyses are also reported for films of potential interest. It was demonstrated that appreciable amounts of barium and calcium could be incorporated in the films strontium was not successfully codeposited. The dielectric films as produced yield properties equivalent or slightly improved over simple anodized films. However, in the case of titanates and niobates, a subsequent vacuum heat treatment coupled with an air oxidation or healing step resulted in films with an order of magnitude improvement of capacitive properties and a consequent improvement in loss and resistive properties. Comparable results have not yet been achieved with zirconates and tantalates.

Subject Categories:

  • Inorganic Chemistry
  • Electricity and Magnetism

Distribution Statement:

APPROVED FOR PUBLIC RELEASE