Techniques for Materials characterization
Code
9477
Academic unit
Faculdade de Ciências e Tecnologia
Department
Departamento de Ciências dos Materiais
Credits
6.0
Teacher in charge
Pedro Miguel Cândido Barquinha
Weekly hours
5
Total hours
66
Teaching language
Português
Objectives
This course has the objective of giving a theoretical and practical training in various techniques for materials characterization such as Optical Microscopy, XRD, XRF, SEM, EDS, FIB, TEM, Infrared and UV-Vis spectroscopy. The main intent is to turn clear to the students at an early stage of their academic path which are the most adequate characterization techniques answering to the questions they have regarding a certain material/device.
Prerequisites
Basic knowledge of chemistry, physics and materials science
Subject matter
XRF and XRD: Bragg Law. Computation of structure factors. Wavelength dispersion spectrometer. X-ray fluorescence spectrometry.
OPTICAL MICROSCOPY: Light. Visible light spectrum and colors. Laws of refraction, reflection and diffraction of light.. Main types of optical microscopes, transmission and reflected microscopes. Basics and main components of an optical light microscope. Convex and concave lenses, the focal length and ray diagrams of a lens. Image of an object. Definition of image resolution and magnification. Optical aberrations of lens. Magnification, numerical aperture and resolving power of a single lens. Illumination system. Optical components: condenser, eyepieces and objective lens. Types of objective lenses (achromat, fluorite or semiapochromat and apochromat lens). Magnification, numerical aperture, and resolving power of objectives lenses. Depth of field. Immersion lenses. Aperture and field diaphragms. Cameras and digital image. Contrast methods in light microscopy: bright field, oblique illumination, dark field, Rheinberg contrast, polarized light, phase contrast and differential interference contrast (DIC). Fluorescence microscopy.
ELECTRON MICROSCOPY: Electron Beam versus Light. Main types of electron microcopes TEM, SEM and STEM. Electron detectors. X-ray detectors. Contrast methods used in SEM. Topographic contrast. Elementary analysis in SEM-EDS/WDS. Focused Ion Beam (FIB)
OPTICAL SPECTROSCOPY: Infrared spectroscopy; Transmission spectroscopy in the near IR, visible, and UV range; Spectroscopic ellipsometry. Characterization of thin films of amorphous silicon and zinc oxide, using these techniques for the determination of the film''s thickness, composition, optical properties (refractive index, optical gap, absorption coefficient, etc..)
Bibliography
Principles of Instrumental analysis, D. Skoog & D. West, 1971
Scanning Electron Microscopy, X-ray Microanalysis and Analytical Electron Microscopy; C. E. Lyman, J. Goldstein, D.E.Newbury et al.
X-ray characterization of materials / Eric Lifshin (ed.). WILEY-VCH Verlag GmbH, 1999
The Physics of Thin Film Optical Spectra: An Introduction Olaf Stenzel (Author), Springer;
Handbook of Infrared Spectroscopy of Ultrathin Films, VP Tolstoy, I Chernyshova, VA. Skryshevsky, Wiley-Blackwell
Spectroscopic Ellipsometry: Principles and Applications, H Fujiwara, VP Tolstoy, Wiley-Blackwell
Teaching method
The program is divided in theoretical and lab classes, 2 and 3 hours per week, respectively, being splited in 4 modules, each one focusing one (or a group) of characterization techniques: XRF-XRD, Optical Microscopy, SEM-EDS-FIB-TEM, spectroscopies.
The thematics are exposed in the lectures with the support of ppts with the basic concepts of the techniques, required tools and aplicability for the analysis of materials and devices.
In the lab classes the students have contact with the characterization techniques focused in the lectures. The main objective is to demonstrate the operation of the techniques using materials produced within the framework of running research projects.
The students are evaluated with two tests and one group report about one the lab works. All the groups answer to a small quiz about each technique (during lab classes)