Dopant spectroscopic studies in II-VI material systems for IR detectors and photovoltaïc cells
type: Dataset
description: This thesis work presents optical and electrical characteristics of dopants in HgCdTe, CdZnTe and CdS layers. These 3 materials II-VI have mutual interest to be used in detection devices, for infrared light detection with HgCdTe and CdZnTe or for visible light detection in the case of CdS. Optical characterization of these II-VI layers was carried out with photoluminescence and was correlated with electrical measurements realized by temperature dependant Hall effect. First, a study of intrinsic doping with mercury vacancies and of extrinsic doping with arsenic in HgCdTe layer, the active layer in infrared detectors, was carried out. To do so, optical measurements by photoluminescence (on an experiment set up in the laboratory during the first thesis year which allows to work from low temperatures to room temperature between 1µm and 12 µm in IR) on HgCdTe layers grown by liquid phase epitaxy (LPE) with different compositions were managed. Correlation between these optical measurements with electrical measurements by temperature dependent Hall measurements led to identify activation energies of the 2 mercury vacancy acceptor levels and to show U-negativity phenomenon of mercury vacancy in HgCdTe. Moreover, comparison between PL spectra of As doped samples during molecular beam epitaxial (MBE) growth with measurements carried out by X-ray absorption (EXAFS) allowed to observe optical recombination associated to the different arsenic complexes formed before and after activation annealing . Besides, a modelling work about alloy disorder phenomenon in HgCdTe was managed. More precisely, a model based on a Gaussian statistic associated to alloy fluctuations around a mean gap and a Boltzmann statistic was developed in order to fit absorption spectra first, then to fit photoluminescence spectra. This model allowed us to fit closely photoluminescence and absorption spectra, taking into account alloy disorder of the material. Thus, we found that spectra fitting with Gaussian f…
issued: 2026-05-13T19:33:22.948309
language: fr
modified: 2026-05-13T19:33:22.948315
contact point: Organization
  fn: CCSD
keyword: cds
keyword: hall-measurements
keyword: hgcdte
keyword: infoeu-reposemanticsdoctoralthesis
keyword: photoluminescence
keyword: spioptiengineering-sciences-physicsoptics--photonic
keyword: theses
landing page: https://theses.hal.science/tel-00796028

Dopant spectroscopic studies in II-VI material systems for IR detectors and photovoltaïc cells
type: Distribution
format: HTML
issued: 2026-05-13T19:33:23.036511
modified: 2026-05-13T19:33:22.904932
access URL: https://theses.hal.science/tel-00796028

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