The GEMaC-Versailles lab is well-known in this field, mainly in the study of “Diamond”, “ZnO” and “Magnetic oxides” in thin films. The common point for all these semiconductors is that they are wide band gap materials (optical band gap>2.5eV), with intrinsic and /or extrinsic strongly localized defect levels. This experimental PhD-thesis will consist first in the conception and realization of the new concept of experiment, so called “4-coefficient in high magnetic field”. This characterization will give possibility (thanks to special geometry of electrical contacts) to measure for the same sample 4 coefficients of electrical transport: Resistivity, Hall constant, Seebeck coefficient and Nernst coefficient. All measurements will be carried out for thin and ultra-thin layers in high magnetic field (± 9T). These measured 4 coefficient will allow us characterize the electronic band structure in the centre of the Brillouin-zone (Fermi energy, effective mass, parameters of scattering). We will study the different materials fabricated in GEMaC (doped ZnO and diamond and Fe2-xTixO3-d or LaNiO3-δ magnetic oxides), presenting a charge carriers’ localization, although it was of different natures. One part of this thesis will concern the lithography in MINERVE CTU in Orsay (with collaboration with P. Lecoeur , IEF-Orsay). This unique experimental set-up, realized during this PhD-thesis will work in 2K-400K temperature range, in 9T magnetic field, provided in NOVATECS platform of GEMaC. The transition between localized and delocalized states of the charge carriers will be studied versus temperature and versus different magnetic fields.
Master degree in Physics of Semiconductors (high score necessary to be selected by grant commission); skills in instrumentation and programming