Structure et propriétés optiques d'oxydes de germanium contenant des nanostructures de germanium et influence de leur dopage à l'erbium

Abstract : This thesis is reporting on the structural and optical characterization of GeOx germanium oxide thin films, of GeOx/SiO2 multilayers, and of the influence of erbium doping in the GeOx:Er thin films. The samples were prepared by evaporation of GeO2 powder and deposition on substrates maintained at 100°C. The films are substoichiometric with the GeO1,5 composition. With annealing treatments, a demixtion phenomenon occurs in the films, according to the reaction GeOx => GeO2 + Ge, which corresponds to the appearance of amorphous germanium aggregates in a GeO2 matrix. For annealing temperatures less than 400°C, the GeOx thin films and the multilayers show a broad band at 800 nm attributed to defects in the GeOx film. This band disappears after a thermal treatment at 400°C and a new band appears at lower energy. This band is attributed to amorphous germanium aggregates confined in the germanium dioxide matrix. The doping of the GeOx films with erbium allows us to observe a photoluminescence signal at 1.54 m characteristic of the 4I13/2 => 4I15/2 transition in the Er3+ ions. It is possible to correlate the intensity of this band to the presence of the band at 800 nm in the doped films, which suggests that an energy transfer mechanism between the band of defects and the level 4I9/2 of the erbium ions. The experiments of passivation with hydrogen confirm this assumption since the passivated undoped films, which do not present any band at 800 nm, do not show either any band at 1.54 micrometers when they are doped.
Document type :
Theses
File URL :
http://docnum.univ-lorraine.fr/prive/SCD_T_2007_0050_ARDYANIAN.pdf
Complete list of metadatas

https://hal.univ-lorraine.fr/tel-01753762
Contributor : Thèses Ul <>
Submitted on : Thursday, March 29, 2018 - 4:48:20 PM
Last modification on : Monday, April 16, 2018 - 10:40:59 AM

Identifiers

  • HAL Id : tel-01753762, version 1

Collections

Citation

Mahdi Ardyanian. Structure et propriétés optiques d'oxydes de germanium contenant des nanostructures de germanium et influence de leur dopage à l'erbium. Autre [cond-mat.other]. Université Henri Poincaré - Nancy 1, 2007. Français. ⟨NNT : 2007NAN10050⟩. ⟨tel-01753762⟩

Share

Metrics

Record views

4