MECHANICAL PROPERTIES OF THIN FILMS. Technical Report No. 29

PDF Version Also Available for Download.

Description

vention of the Society for Nondestructive Testing. The elastic and plastic properties are reviewed with special emphasis on metal films prepared by vacuum evaporation, although work with both non-metals and other preparation techniques is discussed when it is the only existing data or has particular importance. A definite lack of agreement exists among the various workers and as a result detailed explanations are not possible although general suggestions do exist. The structure of thick polycrystalline films is reviewed as it is important to a discussion of the mechanical properties, but the structure is in itseif poorly understood in the case ... continued below

Physical Description

Pages: 74

Creation Information

Hoffman, R W November 1, 1963.

Context

This article is part of the collection entitled: Office of Scientific & Technical Information Technical Reports and was provided by UNT Libraries Government Documents Department to Digital Library, a digital repository hosted by the UNT Libraries. More information about this article can be viewed below.

Who

People and organizations associated with either the creation of this article or its content.

Author

Publisher

Provided By

UNT Libraries Government Documents Department

Serving as both a federal and a state depository library, the UNT Libraries Government Documents Department maintains millions of items in a variety of formats. The department is a member of the FDLP Content Partnerships Program and an Affiliated Archive of the National Archives.

Contact Us

What

Descriptive information to help identify this article. Follow the links below to find similar items on the Digital Library.

Description

vention of the Society for Nondestructive Testing. The elastic and plastic properties are reviewed with special emphasis on metal films prepared by vacuum evaporation, although work with both non-metals and other preparation techniques is discussed when it is the only existing data or has particular importance. A definite lack of agreement exists among the various workers and as a result detailed explanations are not possible although general suggestions do exist. The structure of thick polycrystalline films is reviewed as it is important to a discussion of the mechanical properties, but the structure is in itseif poorly understood in the case of thick fllms. The general behavior may be summarized as follows: The elastic modulus seems to be the same as that of bulk material. Breaking strengths are normally 3 to 7 times larger than those of annealed bulk material and compare with values for very heavily cold-worked samples. Creep is usually observed at relatively low strains. The increased strength undoubtedly arises from a restriction of dislocation motion, as well as source limitations, and in this respect differ from whiskers which often have a low dislocation concentration. The relative importhnce of pinning by point defects or impurities, limitations of dislocation length by the thickness or crystalline size, dislocation interactions and contributions from the oxide layer on the surface are not known. Although some of these should be thickness dependent, all experiments do not show such a trend. Fracture results from the motion of many dislocations leading to a localized thinning and ultimately cracks in the film. Separation of crystallite size and microstrain broadening of diffraction lines has been done in several cases. Stresses may result from differential thermal expansion as well as the film itself. The intrinsic stresses are often tensile, large, and depend strongly on the substrate temperature during deposition and somewhat less strongly on the rate at which the film is formed. Anisotropic stresses are found when the atoms arrive at other than normal incidence. The intrinsic stress may arise from a combination of surface tension and effects between the boundaries of the crystallites. (auth)

Physical Description

Pages: 74

Source

  • 1963 ASM Metals/Materials Show - Cleveland, Ohio - October 21 - 25, 1963

Language

Item Type

Identifier

Unique identifying numbers for this article in the Digital Library or other systems.

  • Report No.: CONF-356-11
  • Grant Number: AT(11-1)-623
  • Office of Scientific & Technical Information Report Number: 4009661
  • Archival Resource Key: ark:/67531/metadc866887

Collections

This article is part of the following collection of related materials.

Office of Scientific & Technical Information Technical Reports

What responsibilities do I have when using this article?

When

Dates and time periods associated with this article.

Creation Date

  • November 1, 1963

Added to The UNT Digital Library

  • Sept. 16, 2016, 12:32 a.m.

Description Last Updated

  • Oct. 31, 2016, 3:17 p.m.

Usage Statistics

When was this article last used?

Congratulations! It looks like you are the first person to view this item online.

Interact With This Article

Here are some suggestions for what to do next.

Start Reading

PDF Version Also Available for Download.

Citations, Rights, Re-Use

Hoffman, R W. MECHANICAL PROPERTIES OF THIN FILMS. Technical Report No. 29, article, November 1, 1963; United States. (digital.library.unt.edu/ark:/67531/metadc866887/: accessed August 22, 2017), University of North Texas Libraries, Digital Library, digital.library.unt.edu; crediting UNT Libraries Government Documents Department.