4/26/2002, Friday Evolution of Surface Roughness

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4/26/2002, FridayEvolution of Surface Roughness
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Model
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Chemical Potential for Roughness Evolution
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Interface Energy Change
Thickness t
g solid-etchant interface energy density
Curvature
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Strain Energy Change
Strain energy difference w0 is the strain energy
of flat surface
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Etching Rate
g solid-etchant interface energy density
Curvature
Strain energy difference w0 is the strain energy
of flat surface
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Competition of Two Tendencies
Surface energy g
Residual stress?s
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Interface Energy Influence on Roughness Evolution
Surface energy g
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Strain Energy Influenceon Roughness Evolution
Residual stress?s
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Frequency Dependency ofInterface Energy Change
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Frequency Dependency ofStrain Energy Change
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Frequency Dependency ofEtching Rate
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Roughness Evolution Pattern
Stress state
Material parameters