Tutorials

Two tutorials on the topics of "Growth of group III-nitride materials" and "Point defects" will be offered on Sunday afternoon, August 23rd, 2020. The tutorials will be given by Ferdinand Scholz, University of Ulm (Germany), and Chris van de Walle, University of California at Santa Barbara (USA), respectively. All attendees of IWN 2020 can book this option when registering via the IWN 2020 website.


Ferdinand Scholz

Epitaxial growth of nitride heterostructures

In this tutorial  we will briefly discuss the basics of modern epitaxial methods with strong focus on metalorganic vapor phase epitaxy.
This method is excellently suited to grow sophisticated heterostructures including quantum wells and even structures of lower dimensions, as it provides fairly independent control over each of the components forming such layers. Today, it is by far the most important tool for the growth of GaN-based devices like LEDs, laser diodes, transistors etc. Special focus will be set to some challenges growing particularly these materials, e.g. the reduction of the huge dislocation density in GaN layers grown on foreign substates.


Chris van de Walle

Characterization and calculation of point defects

Point defects and impurities affect or even completely determine physical and chemical properties of semiconductors.  Characterization of point defects based on experimental techniques alone is often inconclusive. In such cases, the combination of experiment and theory is crucial to gain understanding of the system studied. In this tutorial, I will explain how and when such comparison provides new understanding of the defect physics [1]. I will focus on processes that can be analyzed or understood in terms of configuration coordinate diagrams of defects in their different charge states. These processes include light absorption, luminescence, and nonradiative capture of charge carriers.

[1] A. Alkauskas, M. D. McCluskey, and C. G. Van de Walle, J. Appl. Phys. 119, 181101 (2016).