Técnicas de Caracterização de Materiais

Semester: 
Fall
Offered: 
2016

Techniques for Materials Characterization

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.

Optical Spectroscopy (Rita Branquinho)

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..)

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)