Origin and Control of Residual Stresses in Atomically Deposited Materials.
Abstract
For the first portion of the program, 'The Origin and Control of Residual Stress in Atomically Deposited Materials', the emphasis was placed on identifying the origin of residual stress in the model material CVD-SiC. The initial assumption was that the origin of the residual stress could be correlated with growth morphology. Parameters such as temperature, hydrogen/silane ratios, flow rates, pressure and reactant species were varied in an attempt to reveal the stress/morphology relationship. No apparent pattern emerged based on the initial assumption, but a relationship did become evident between extraneous gases and residual stress. This result required that the study program be recast along new lines that would emphasize measurement of the influence of additions of gases such as nitrogen and oxygen. Equipment was designed and set up to produce 1 in. diameter sample tubes of CVD-SiC. The arrangement permitted additions of various extraneous gases to the deposition species at concentrations that would exaggerate their influence on residual stress. This revised program has been proposed to be conducted during the next phase of the work. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Nov 29, 1977
- Accession Number
- ADA049195
Entities
People
- Richard E. Engdahl