MATSE 405: Microstructural Characterization

Homepage: http://userweb.mrl.uiuc.edu/cahill/405/matse405.html

Textbook: "The Basics of Crystallography and Diffraction," by C. Hammond (2nd edition, Oxford University Press, 2001).

References: B. D. Cullity, "Elements of X-Ray Diffraction," Addison-Wesley, 1956.
C. J. Ball, "An Introduction to the Theory of Diffraction," Pergamon Press, 1971.
W. T. Welford, "Optics," Oxford University Press, 1981.

Catalog Description:

Studies the fundamentals and applications of various forms of microscopy (image formation) and diffraction for characterization of physical microstructure of materials and of various forms of spectroscopy for characterization of chemical microstructure. Prerequisites: Physics 114, Chemistry 102, and Materials Science and Engineering 201. 3 hours or 3/4 unit. 2 hours lecture, 3 hours laboratory/week

Course Topics:

1. Geometrical optics
2. Crystal structures
3. Complex notation for wave amplitudes and phase
4. Diffraction from one-dimensional objects and crystals
5. Diffraction from two- and three-dimensional crystals
6. Reciprocal lattices and Ewald sphere constructions for x-ray and electron diffraction
7. Resolution in microscopy
8. Contrast in microscopy: bright-field, dark-field, and phase contrast
9. Atomic scattering factors for photons, electrons, and neutrons
10. Dynamical effects: index of refraction and extinction
11. Core-level atomic physics and spectroscopic notation
12. Cross-sections for core-level impact ionization and photoemission
13. Microprobe analysis and x-ray photoelectron spectroscopy

Laboratory Work:

1. Optical diffraction and microscopy
(a) geometrical optics of image formation
(b) transmission and reflection microscopes
(c) diffraction from a two-dimensional crystal (TEM grid)
(d) diffraction from a one-dimensional object, coherent diffraction
(e) resolution in microscopy; bright-field, dark-field contrast
(f) optical microscopy of paraffin film dewetting and crystallization

2. X-ray powder diffraction
(a) fcc crystals and angular resolution of the diffractometer
(b) random and systematic errors, lattice parameter refinement
(c) structure factors and atomic scattering factors using NaCl structure crystals
(d) strain and peak-widths due to inhomogeneous strain and finite crystal size
(e) hcp crystals, preferred orientation in coatings
(f) x-ray absorption

Computer Usage: Extensive use of Windows PCs for data acquisition and analysis

Course Objectives:

1. To teach students the science of microscopy and diffraction based on the physical optics of scalar waves and elastic scattering of waves from atoms.
2. To teach students how the design and performance of simple microscopes and diffractometers is based in the fundamentals of geometrical and physical optics.
3. To teach students diffraction from simple objects and crystals in one-, two-, and three-dimensions.
4. To extend students knowledge of the mathematics of complex variables.
5. To give students hands-on experience in the operation of powder diffractometers for studying the microstructure of materials
6. To give students hands-on experience in the use of optical bench components for optical metrology.
7. To teach students the fundamentals of core-level spectroscopy for microanalysis and surface analysis.

Course Outcomes:

1. Given a powder specimen of a material with a simple crystal structure, be able to collect, analyze and understand powder diffraction data.
2. Be able to describe the construction of transmission and reflection optical microscope, the factors that control resolution, and contrast mechanisms.
3. Be able to calculate intensities of a microscope image of a one-dimensional diffraction grating using bright-field, dark field, and phase contrast apertures.
4. Be able to use Ewald sphere constructions and calculations of structure factors to predict diffraction conditions and intensities from a three-dimensional crystal.
5. Be able to calculate estimates of x-ray mass absorption coefficients at x-ray energies.
6. Be able to calculate estimates of electron extinction lengths in transmission electron microscopy.

Assessment Tools:

1. Weekly problem sets (18%)
2. Weekly laboratory reports (18%)
3. Two, midterm exams during the 6th and 12th weeks of the semester (32%)
4. Final exam (32%)

Contribution of Course to Meeting the Professional Component:

100%

Prepared by:

David Cahill, July 2003