Accession Number : ADD003436

Title :   Method for Forming Uniform Stress-Free Thin Films.

Descriptive Note : Patent,

Corporate Author : DEPARTMENT OF THE NAVY WASHINGTON D C

Personal Author(s) : Anderson,Gordon Wood

Report Date : 08 Jun 1976

Pagination or Media Count : 5

Abstract : The patent relates to stress free films of metals, semiconductors and insulators which have a very uniform thickness and composition and which are supported independent of a substrate, and the method of forming same. Such films have wide application for reflection of light as mirrors and transmission or absorption of light in the form of filters throughout the complete optical spectrum. Also, such films may be used for the study of fundamental properties of the material in question. As an example of forming a uniform, stress-free, thin film of an amorphous germanium film, the molybdenum grid-tantalum structure with the collodion film deposited thereon is placed into an ultra high vacuum system for deposition of the germanium film. The germanium is deposited at a slow deposition rate of from 1-10 angstroms per second with the collodion-grid support at least 6 cm and typically 10 cm or more from the germanium source to ensure uniform deposition.

Descriptors :   *Deposition, *Optical coatings, *Patents, Thin films, Semiconducting films, Metal films, Electrical insulation, Mirrors, Substrates, Tantalum, Germanium, Grids, Molybdenum, Amorphous materials

Subject Categories : Metallurgy and Metallography
      Optics
      Solid State Physics

Distribution Statement : APPROVED FOR PUBLIC RELEASE