EP3 Friday Seminar WN26 2024

Abschlussvortrag im Rahmen des Habilitationsverfahrens

Dr. Johannes Kleinlein

Universität Würzburg, Lehrstuhl für Experimentelle Physik III

Titel

Lithographic fabrication of mercury telluride-based heterostructure devices – from micro- to nanostructure dimensions

Datum:                 28.06.2024

Uhrzeit:                15:45 Uhr

Ort:                       Röntgen-Hörsaal (Physikalisches Institut)

Abstract

At the chair of Experimental Physics III, we grow mercury telluride-based heterostructures by molecular beam epitaxy with single crystal quality. Our fundamental studies based on electrical transport experiments require lithographically defined device structures. To explore all facets of the mercury telluride material system, it is crucial to maintain intrinsic material properties including the presence of topological surface states, charge carrier densities and their mobility throughout the fabrication process.

This presentation provides an overview of the significant advances in the microfabrication of mercury telluride-based heterostructure devices that have been made over the past few years. The following topics are addressed in particular: patterning of mesa structures, fabrication of ohmic contacts, and gate dielectrics based on low-temperature atomic layer deposition. A series of exemplary device structures is discussed, ranging from macroscopic Hall bar structures with typical dimensions of hundreds of micrometers to nanostructured features with dimensions down to ~10 nm.