Electron Microscopy and Diffraction

The course is given every second year, and is given autumn 2025. The course covers theory and background for advanced analysis techniques in transmission electron microscopy (TEM) and electron diffraction. An introduction course is compulsory for students who have no experience in TEM, such a course is given in the beginning of the semester. Main topics of the main part are:

i) Diffraction theory, including kinematic theory, dynamical theory, dispersion surfaces, many beam solutions, and absorption effects.

ii) Contrast analysis in microscopy with use in high resolution microscopy.

iii) Theory of HAADF/STEM (high angle annular dark field/scanning TEM).

iv) Aberrations in electron optics.

v) Theory behind advanced spectroscopy analysis techniques such as EELS (electron energy loss spectroscopy).

vi) Electron detection, principles and types of detectors.

The students should learn and understand the underlying theory in transmission electron microscopy and electron diffraction.

From the first introductory part of the course, the students should know:

• how electrons interact with materials
• how the electron beam is controlled and altered in a TEM
• why electron diffraction is so important in TEM
• what contrast mechanisms we have in TEM
• how the different analytical techniques work and are used in a TEM

From the second, more advanced part of the course, the students should learn:

• how to derive the dynamical theory of electron diffraction in perfect crystals
• the theory behind high-resolution electron microscopy
• the different types of aberrations in the TEM and how they affect image formation
• the contrast mechanisms in high angle annular dark field scanning TEM
• how an electron energy loss spectrum is made and what the different energy losses in the spectra mean.
• how electrons are detected and principles for the different electron detectors.

The students will give lectures to fellow students and the content will be discussed. The lectures provide an introduction to the different experimental techniques described under "academic content". When lectures and lecture material are in English, the exam may be given in English only.