Investigation of the charge carrier and heat transport in model systems for band gap engineering of thin films and heterostructures based on In2O3, Ga2O3 and/or Al2O3. The specific heterointerfaces are chosen according to the availability—as provided by the growth cluster C3—and on behalf of existing structural investigations which prove the high-quality of the interfaces. Methods: Thin film and heterolayer device processing via microlithography and etching. Exfoliation of single crystals for preparation of single crystalline thin film samples. Ohmic contact preparation in Van-der-Pauw and Hallbar geometry. Back gate and or top gate preparation. Measurement of the longitudinal and Hall electrical resistance in the regime of < 4 K to 450 K in applied magnetic and electrical fields. Determination of the thermal conductivity by 3ω- or 2ω-methods.
Major accomplishments expected:
Determination of temperature-dependent electrical and thermal conductivity. Separation of conductivity contributions in the case of heterolayers. Identification of scattering and transport mechanisms of charge and heat in thin films and at heterointerfaces.
Collaboration with partners in the project:
Cluster C3 “Fundamentals of Growth”, i.e. Günther Wagner and Oliver Bierwagen.
Collaboration with other clusters a collaboration is highly favourable, in particular with C4 “Atomic defects, doping and defect engineering” and later on with regards to the fabrication of devices with FBH and UL.
Johannes Boy obtained his BSc in 2014, and his MSc in the beginning of 2017, both at Humboldt University; Berlin. In his master's thesis he has investigated the influence of in-plane electric fields on the magnetotransport properties in narrow-gap semiconductor nanostructures. His focus lay on the transmission of quantum Hall edge channels through electrostatic constrictions. He is looking foreward to investigate the electric and thermoelectric transport properties of thin oxide layers.
If you have queries about the project, please contact the PI:
Saskia Fischer, Humboldt-Universität zu Berlin
The Leibniz ScienceCampus GraFOx is a network of two Leibniz Institutes, two universities and one institute of the Max Planck Society. It is based in Berlin, Germany.
Paul-Drude Institut für Festkörperelektronik (PDI)
Leibniz-Institut im Forschungsverbund Berlin e.V.
Tel.: +49 30 20377-342
Prof. Dr. Henning Riechert, PDI
Dr. Oliver Bierwagen, PDI
Dr. Martin Albrecht, IKZ