Course detail
Particle Optics and Electron Microscopy
FSI-TCO Acad. year: 2023/2024 Winter semester
The course deals with problems of optics of charged particles in focusing and deflection systems and spectrometers. The sources of electrons and ions are characterized as well as electron and ion optical elements and instruments utilizing the beams of charged particles. In addition to the practical implementation of individual elements, the theory of imaging and aberrations is emphasized to allow students effectivelly use software for design of charged particle systems.
Language of instruction
Czech
Number of ECTS credits
5
Supervisor
Department
Entry knowledge
Knowledge of electromagnetism on the level defined by the textbook HALLIDAY, D. – RESNICK, R. – WALKER, J.: Fundamentals of Physics. J. Wiley and Sons. MATHEMATICS: Basics of vector analysis.
Rules for evaluation and completion of the course
Active participation at tutorials and correct protocols. Exam is oral, two questions from the list of subjects given above. The preparation takes 30 minutes, lecture notes and literature are allowed.
Compulsory participation at tutorials, protocol with solution of all sample problems and on CAD projects. Auxiliary lecture notes will be provided to the students on Internet.
Aims
The course improves the knowledge of the students about the most important instruments used in microscopy and microanalysis, in electron and ion beam technology and in the physics of surfaces and thin films.
Knowledge of motion of charged particles in electromagnetic fields of electron and ion lenses, deflectors and spectrometers as well as the knowledge of instruments using them for microscopic or technological applications.
The study programmes with the given course
Programme N-FIN-P: Physical Engineering and Nanotechnology, Master's, compulsory
Programme N-PMO-P: Precise Mechanics and Optics, Master's, compulsory
Type of course unit
Lecture
26 hours, optionally
Teacher / Lecturer
Syllabus
Overview of instruments utilizing the beams of charged particles for the study of structure and composition of solids and in technological applications.
Wave and relativistic properties of charged particles. Equation of motion for charged particles in electrostatic and magnetic fields.
Qualitative description of electrostatic and magnetic lenses and deflectors, based on equation of motion.
The series expansion of potential near an optical axis. Multipole fields for particle optics and their realization.
General expression of trajectory equation for systems with straight axis.
Paraxial equation for rotationally symmetric and quadrupole lenses and for lenses with deflection systems.
Aberrations of charged particle optical systems.
Transport of particles – the use of matrix notation. The description of particle optics with variational methods (Lagrange function, index of refraction) and with Hamiltonian methods.
Basic numerical methods of computing fields in electron optics and their optical properties.
Sources of electrons and ions. Basic properties and utilization.
Scanning electron microscope – the principle of image formation, depth of field, dependence of spot current on spot size, image resolution.
Image formation in a transmission electron microscope, the image resolution.
Optics of systems with curved axis, electron and ion spectrometers – basic types and properties.
Exercise
14 hours, compulsory
Syllabus
Electron movement in the homogeneous electrostatic and magnetic field
Derivation of trajectorz equation and paraxial equation
Expansion of the potential near optical axis
Geometric aberrations of 3rd order of electrostatic and magnetic lens
Spherical aberration of magnetic lens
Computer-assisted exercise
12 hours, compulsory
Teacher / Lecturer
Syllabus
Aberration polynomial – visualisation of aberrations, spot size, resolution
Finite element method – solution of 1D electrostatic field
Intoduction to EOD (Electron Optical Design) software
EOD – electrostatic lens design, focussing, computation of aberrations
EOD – magnetic lens and deflectors
Work on individial project