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Professor David Attwood / UC Berkeley / Iranian Light Source Workshop / March 3-4, 2014 ILSW_Attwood_Lec4_March2014.pptx
X-Ray Interaction with Matter: Absorption, Scattering and
Refraction
David Attwood University of California, Berkeley
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Professor David Attwood / UC Berkeley / Iranian Light Source Workshop / March 3-4, 2014 ILSW_Attwood_Lec4_March2014.pptx
The short wavelength region of the electromagnetic spectrum
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n = 1 – δ + iβ δ, β << 1
Professor David Attwood / UC Berkeley / Iranian Light Source Workshop / March 3-4, 2014 ILSW_Attwood_Lec4_March2014.pptx
Photon energy, wavelength, power
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Professor David Attwood / UC Berkeley / Iranian Light Source Workshop / March 3-4, 2014 ILSW_Attwood_Lec4_March2014.pptx
Characteristic absorption edges for almost all elements in this spectral region
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Professor David Attwood / UC Berkeley / Iranian Light Source Workshop / March 3-4, 2014 ILSW_Attwood_Lec4_March2014.pptx
Energy levels, quantum numbers, and allowed transitions for the copper atom
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Professor David Attwood / UC Berkeley / Iranian Light Source Workshop / March 3-4, 2014 ILSW_Attwood_Lec4_March2014.pptx
Electron binding energies, in electron volts (eV), for the elements in their natural forms
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www.cxro.LBL.gov
Professor David Attwood / UC Berkeley / Iranian Light Source Workshop / March 3-4, 2014 ILSW_Attwood_Lec4_March2014.pptx 7
Refractive index from the IR to the x-ray region of the electromagnetic spectrum
Professor David Attwood / UC Berkeley / Iranian Light Source Workshop / March 3-4, 2014 ILSW_Attwood_Lec4_March2014.pptx
Refractive index at nanometer wavelengths
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Professor David Attwood / UC Berkeley / Iranian Light Source Workshop / March 3-4, 2014 ILSW_Attwood_Lec4_March2014.pptx
Available optical techniques for soft x-rays and EUV
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Professor David Attwood / UC Berkeley / Iranian Light Source Workshop / March 3-4, 2014 ILSW_Attwood_Lec4_March2014.pptx 10
Charles-Augustin de
Coulomb
Carl Friedrich Gauss
Michael Faraday
André-Marie Ampère James Clerk
Maxwell
Heinrich Hertz
Maxwell’s Equations
Courtesy of Andrew Aquila (AS&T, UC Berkeley)
The Equations of Light
Professor David Attwood / UC Berkeley / Iranian Light Source Workshop / March 3-4, 2014 ILSW_Attwood_Lec4_March2014.pptx
Scattering, refraction, and reflection
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Professor David Attwood / UC Berkeley / Iranian Light Source Workshop / March 3-4, 2014 ILSW_Attwood_Lec4_March2014.pptx
Scattering cross-sections
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Professor David Attwood / UC Berkeley / Iranian Light Source Workshop / March 3-4, 2014 ILSW_Attwood_Lec4_March2014.pptx
Scattering by a bound electron
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Professor David Attwood / UC Berkeley / Iranian Light Source Workshop / March 3-4, 2014 ILSW_Attwood_Lec4_March2014.pptx
Example: complex atomic scattering factor for carbon
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Professor David Attwood / UC Berkeley / Iranian Light Source Workshop / March 3-4, 2014 ILSW_Attwood_Lec4_March2014.pptx
Wave propagation and refractive index at x-ray wavelengths
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Professor David Attwood / UC Berkeley / Iranian Light Source Workshop / March 3-4, 2014 ILSW_Attwood_Lec4_March2014.pptx
Refractive index in the x-ray spectral region
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Professor David Attwood / UC Berkeley / Iranian Light Source Workshop / March 3-4, 2014 ILSW_Attwood_Lec4_March2014.pptx
Refractive index for x-rays
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Professor David Attwood / UC Berkeley / Iranian Light Source Workshop / March 3-4, 2014 ILSW_Attwood_Lec4_March2014.pptx
Quantum mechanical model of refractive index
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Professor David Attwood / UC Berkeley / Iranian Light Source Workshop / March 3-4, 2014 ILSW_Attwood_Lec4_March2014.pptx 19
Phase variation and absorption of propagating waves
Professor David Attwood / UC Berkeley / Iranian Light Source Workshop / March 3-4, 2014 ILSW_Attwood_Lec4_March2014.pptx 20
Phase shift relative to vacuum propagation
Professor David Attwood / UC Berkeley / Iranian Light Source Workshop / March 3-4, 2014 ILSW_Attwood_Lec4_March2014.pptx 21
Spatial continuity along the interface
Professor David Attwood / UC Berkeley / Iranian Light Source Workshop / March 3-4, 2014 ILSW_Attwood_Lec4_March2014.pptx 22
Normal incidence reflection at an interface (both polarizations)
Professor David Attwood / UC Berkeley / Iranian Light Source Workshop / March 3-4, 2014 ILSW_Attwood_Lec4_March2014.pptx
Glancing Incidence Optics
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Professor David Attwood / UC Berkeley / Iranian Light Source Workshop / March 3-4, 2014 ILSW_Attwood_Lec4_March2014.pptx 24
Total external reflection of soft x-ray and EUV radiation
Professor David Attwood / UC Berkeley / Iranian Light Source Workshop / March 3-4, 2014 ILSW_Attwood_Lec4_March2014.pptx 25
Total external reflection with finite β
Professor David Attwood / UC Berkeley / Iranian Light Source Workshop / March 3-4, 2014 ILSW_Attwood_Lec4_March2014.pptx
X-Rays and Extreme Ultraviolet (EUV) Radiation
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• Optics behave differently at these very short wavelengths (nanometers rather than 520 nm green light)
• The refractive index is less than unity, n = 1 – δ + iβ • Waves bend away form the normal at an interface • Absorption is significant in all materials and at all wavelength. • Because of absorption, refractive lenses do not work, except at
high photon energies ≥ 20 keV. • Because light is bent away from the surface normal, it is possible to
have “total external reflection” at glancing incidence – a commonly used technique.
Professor David Attwood / UC Berkeley / Iranian Light Source Workshop / March 3-4, 2014 ILSW_Attwood_Lec4_March2014.pptx
Buried, trace amounts of iron in a defective silicon solar cell
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Professor David Attwood / UC Berkeley / Iranian Light Source Workshop / March 3-4, 2014 ILSW_Attwood_Lec4_March2014.pptx
X-ray microprobe at SPring-8
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Undulator DCM
TC1Slit Incident Slit
Ion chamber Mirror manipulator
SDD
Sample & Scanner
PIN photodiode
Beam monitor
Optical microscope
Front end
Experimental hutch
98m f1: 252mm
f2: 150mm
45m
Courtesy of K. Yamauchi and H. Mimura, Osaka University.
S. Matsuyama et al., Rev. Sci. Instrum. 77, 103102 (2006)
Now focused to 7 nm
Professor David Attwood / UC Berkeley / Iranian Light Source Workshop / March 3-4, 2014 ILSW_Attwood_Lec4_March2014.pptx
Scattering by density variations within a multilayer coating
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Professor David Attwood / UC Berkeley / Iranian Light Source Workshop / March 3-4, 2014 ILSW_Attwood_Lec4_March2014.pptx
Multilayer mirrors can provide high reflectivity at the Bragg condition
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Professor David Attwood / UC Berkeley / Iranian Light Source Workshop / March 3-4, 2014 ILSW_Attwood_Lec4_March2014.pptx
Atomic scattering factors for silicon (Z = 14)
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Professor David Attwood / UC Berkeley / Iranian Light Source Workshop / March 3-4, 2014 ILSW_Attwood_Lec4_March2014.pptx
Atomic scattering factors for molybdenum (Z = 42)
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Professor David Attwood / UC Berkeley / Iranian Light Source Workshop / March 3-4, 2014 ILSW_Attwood_Lec4_March2014.pptx
A High Quality Mo/Si Multilayer Mirror
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N = 40 d = 6.7
Courtesy of Sasa Bajt (DESY) ˇ
Small reflections at many interfaces add in phase at the Bragg angle
Professor David Attwood / UC Berkeley / Iranian Light Source Workshop / March 3-4, 2014 ILSW_Attwood_Lec4_March2014.pptx
High reflectivity, thermally and environmentally robust multilayer coatings for high throughput EUV lithography
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Professor David Attwood / UC Berkeley / Iranian Light Source Workshop / March 3-4, 2014 ILSW_Attwood_Lec4_March2014.pptx
Multilayer mirrors have achieved 70% reflectivity
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Courtesy of Sasa Bajt, LLNL
Professor David Attwood / UC Berkeley / Iranian Light Source Workshop / March 3-4, 2014 ILSW_Attwood_Lec4_March2014.pptx
The Cassegrain Telescope with multilayer coatings for EUV imaging of the solar corona
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