Plastic Properties of Thin Films on Substrates as Measured by Sub-Micron Indentation Hardness and Substrate Curvature Techniques,
Abstract
Substrate curvature and sub-micron indentation measurements have been used recently to study plastic deformation in thin films on substrates. Both of these techniques have been employed to study the strength of aluminum and tungsten thin films of silicon substrates. In the case of aluminum films of silicon substrates, the film strength is found to increase with decreasing thickness. Grain size variations with film thickness do not account for the variations in strength. Wafer curvature measurements give strengths higher than those predicted from hardness measurements suggesting the substrate thickness may be due to image forces on dislocations in the film due to the elastically stiffer silicon substrate. For sputtered tungsten films, where the substrate plays a role in strengthening the film. The observed strengthening effect with decreased thickness may be due to image forces on dislocations in the film due to elasticity stiffer silicon substrate. For sputtered tungsten films, where substrate is less stiff than the film, the film strength decreases with decreasing film thickness.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 01, 1986
- Accession Number
- ADA177174
Entities
People
- D. S. Gardner
- M. F. Doerner
- W. D. Nix
Organizations
- Stanford University