Synthetic HRTEM images are simulated using Jems® simulation software with a model specimen consisting of a film of strained silicon on top of a relaxed Si0.82Ge0.18 alloy substrate in the [110] zone axis, where biaxial tensile strain exists in the strained silicon layer. Two simulated models are created: one with a sudden change in lattice
constant (strained Si on a “fat” Si substrate) and another with a sudden change in atomic
number (strained Si on a Cl substrate) in order to separate the effects of strain
discontinuities from atomic number discontinuities measuring strain using Geometric Phase Analysis (GPA). The simulated models are subjected to image processing using
GPA software developed by Chung. Two dimensional strain maps are reconstructed and the local strain is determined. Further, an analysis is done to evaluate the best imaging conditions for strain measurement using GPA at heteroepitaxial interfaces.
In addition, the behavior of GPA across a step function in strain or atomic number is examined for information about (a) spatial resolution, (b) the effects of a sudden change in atomic number, (c) instrument parameters, and (d) specimen thickness for a
300KeV TEM. / text
| Identifer | oai:union.ndltd.org:UTEXAS/oai:repositories.lib.utexas.edu:2152/ETD-UT-2009-12-586 |
| Date | 05 August 2010 |
| Creators | Rajagopalan, Srivaramangai |
| Source Sets | University of Texas |
| Language | English |
| Detected Language | English |
| Type | thesis |
| Format | application/pdf |
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