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Titre : Elaboration de couches minces ZnO par ablation laser et caractérisation physique Type de document : texte imprimé Auteurs : Fouad Kermiche, Auteur ; A. Bouabellou, Directeur de thèse Editeur : Constantine : Université Mentouri Constantine Année de publication : 2015 Importance : 129 f. Format : 30 cm. Note générale : 2 copies imprimées disponibles
Langues : Français (fre) Tags : Sciences des matériaux ZnO couche mince ZnO dopé aluminium PLD RBS M-lines Effet hall thin films aluminum doped ZnO Hall Effect ????? ????? ????????? ????????? ??????? PLD ???????
??????? (RBS) ??????? ?????? ???????Lines-M ??? ??? ( Hall Effet"Index. décimale : 530 Physique Résumé : Our thesis aims to achieve and study of the physical properties (Structural, morphological, optical and electrical) of conductive and transparent thin layers of undoped zinc oxide (ZnO) and doped aluminum (AZO) prepared by the pulsed laser deposition technique (PLD) on glass and silicon substrates heated to 450°C.
The source used is a KrF excimer laser (248 nm, 25 ns, 2 J/cm2). The structural study by X-ray diffraction (XRD) showed that these layers has a hexagonal crystal structure with a preferential growth according to the (002) orientation, and a decrease in grain sizes of about 40 to 25 nm with increasing aluminum doping rates of 0 to 5 at%.
leading to a deterioration of the crystalline quality of the layers. The Atomic Force Microscope AFM was used to study the state of the surfaces and their roughness which was found to be between 3 and 15 nm. Rutherford backscattering spectroscopy RBS was used to determine the chemical composition and thickness of the prepared
films, the layer thickness ranges from about 179-366 nm. Study by UV-visible spectrophotometry showed that the transmittance of the samples is around 75% in visible with an optical band gap varying from 3.23 to 3.36 eV when the content of Al doping increases from 0 to 5 at.%. Analysis by (M-Lines) helped us to extract approximate values for the refractive index of these layers, which is between 1.83 and 1.97, and thicknesses very close from those estimated by the RBS analysis, as well as the possibility of using the layers in the field of the optical waveguide. In addition to these results, the electrical measurements by (Hall Effect) have shown that all the layers prepared in this study are n-type semiconductor, and that, the aluminum doping increases the concentration of charge carriers and reduces resistance.
Diplôme : Doctorat en sciences En ligne : ../theses/physique/KER6718.pdf Format de la ressource électronique : Permalink : https://bu.umc.edu.dz/md/index.php?lvl=notice_display&id=9905 Elaboration de couches minces ZnO par ablation laser et caractérisation physique [texte imprimé] / Fouad Kermiche, Auteur ; A. Bouabellou, Directeur de thèse . - Constantine : Université Mentouri Constantine, 2015 . - 129 f. ; 30 cm.
2 copies imprimées disponibles
Langues : Français (fre)
Tags : Sciences des matériaux ZnO couche mince ZnO dopé aluminium PLD RBS M-lines Effet hall thin films aluminum doped ZnO Hall Effect ????? ????? ????????? ????????? ??????? PLD ???????
??????? (RBS) ??????? ?????? ???????Lines-M ??? ??? ( Hall Effet"Index. décimale : 530 Physique Résumé : Our thesis aims to achieve and study of the physical properties (Structural, morphological, optical and electrical) of conductive and transparent thin layers of undoped zinc oxide (ZnO) and doped aluminum (AZO) prepared by the pulsed laser deposition technique (PLD) on glass and silicon substrates heated to 450°C.
The source used is a KrF excimer laser (248 nm, 25 ns, 2 J/cm2). The structural study by X-ray diffraction (XRD) showed that these layers has a hexagonal crystal structure with a preferential growth according to the (002) orientation, and a decrease in grain sizes of about 40 to 25 nm with increasing aluminum doping rates of 0 to 5 at%.
leading to a deterioration of the crystalline quality of the layers. The Atomic Force Microscope AFM was used to study the state of the surfaces and their roughness which was found to be between 3 and 15 nm. Rutherford backscattering spectroscopy RBS was used to determine the chemical composition and thickness of the prepared
films, the layer thickness ranges from about 179-366 nm. Study by UV-visible spectrophotometry showed that the transmittance of the samples is around 75% in visible with an optical band gap varying from 3.23 to 3.36 eV when the content of Al doping increases from 0 to 5 at.%. Analysis by (M-Lines) helped us to extract approximate values for the refractive index of these layers, which is between 1.83 and 1.97, and thicknesses very close from those estimated by the RBS analysis, as well as the possibility of using the layers in the field of the optical waveguide. In addition to these results, the electrical measurements by (Hall Effect) have shown that all the layers prepared in this study are n-type semiconductor, and that, the aluminum doping increases the concentration of charge carriers and reduces resistance.
Diplôme : Doctorat en sciences En ligne : ../theses/physique/KER6718.pdf Format de la ressource électronique : Permalink : https://bu.umc.edu.dz/md/index.php?lvl=notice_display&id=9905 Exemplaires
Code-barres Cote Support Localisation Section Disponibilité aucun exemplaire Etude structurale et optique de films minces ZnO élaborés par voie physique et/ou chimique / Adel Taabouche
Titre : Etude structurale et optique de films minces ZnO élaborés par voie physique et/ou chimique Type de document : texte imprimé Auteurs : Adel Taabouche, Auteur ; A. Bouabellou, Directeur de thèse Editeur : Constantine : Université Mentouri Constantine Année de publication : 2015 Importance : 107 f. Format : 30 cm. Note générale : 2 copies imprimées disponibles
Langues : Français (fre) Tags : Sciences des matériaux Couche mince ZnO PLD Spray DRX AFM RBS M-lines UV-visible Effet Hall Thin films XRD Hall Effect ????? ????? ????????? ??????? ???? ??? ?????? ?????? ??????
??????? ??????? ??????? ??????? ?????? ??????? ??? ???Index. décimale : 530 Physique Résumé : In the present work, we have studied essentially the structural and optical properties of ZnO thin films elaborated using the physical technique s of the pulsed laser ablation (PLD) and the chemical method of the ultrasonic spray pyrolysis.
We have prepared undoped (ZnO) and cobalt-doped zinc oxide (CZO) thin films (Co: 3,5 at.%) by means of the PLD method. Synthesized films have been deposited on glass and silicon substrates heated at 450°C. The used source was a KrF eximer laser (248 nm, 25 ns, 2 J ⁄cm2). Different experimental techniques have been carried out to analyze the fabricated films: the X-ray diffraction (XRD), atomic force microscopy (AFM), Rutherford Backscattering spectrometry (RBS), UV-visible spectrophotometry, M-lines
spectroscopy and Hall effect.
While the ZnO films obtained by the ultrasonic spray technique have been deposited with different deposition times (10, 20, 30 min) on a glass substrate heated at 410 °C, and then they have characterized by XRD, AFM, UV-visible, M-lines and hall effect techniques.
The carried out study shows that all the prepared zinc oxide films have a hexagonal wurtzite-type structure and a preferentially oriented along the direction (002) confused with the c-axis perpendicular to the surface of the substrates. The grain sizes deducted from the XRD measurements vary between 24 and 40 nm. The optical coupling analysis realized by M-lines show that the ZnO films are monomode (for both TE and TM polarizations). However, the undoped ZnO film obtained by PLD is found to be two
guiding modes for TM. The films obtained have an optical transmission of 70 to 90% in the visible region of the spectrum and an optical band gap varying from 3.18 to 3.37 eV.
The electrical conductivity and the concentration of carriers, deduced from Hall effect measurements, are relatively low namely for the films prepared by spray pyrolysis technique.
Diplôme : Doctorat en sciences En ligne : ../theses/physique/TAA6719.pdf Format de la ressource électronique : Permalink : https://bu.umc.edu.dz/md/index.php?lvl=notice_display&id=9904 Etude structurale et optique de films minces ZnO élaborés par voie physique et/ou chimique [texte imprimé] / Adel Taabouche, Auteur ; A. Bouabellou, Directeur de thèse . - Constantine : Université Mentouri Constantine, 2015 . - 107 f. ; 30 cm.
2 copies imprimées disponibles
Langues : Français (fre)
Tags : Sciences des matériaux Couche mince ZnO PLD Spray DRX AFM RBS M-lines UV-visible Effet Hall Thin films XRD Hall Effect ????? ????? ????????? ??????? ???? ??? ?????? ?????? ??????
??????? ??????? ??????? ??????? ?????? ??????? ??? ???Index. décimale : 530 Physique Résumé : In the present work, we have studied essentially the structural and optical properties of ZnO thin films elaborated using the physical technique s of the pulsed laser ablation (PLD) and the chemical method of the ultrasonic spray pyrolysis.
We have prepared undoped (ZnO) and cobalt-doped zinc oxide (CZO) thin films (Co: 3,5 at.%) by means of the PLD method. Synthesized films have been deposited on glass and silicon substrates heated at 450°C. The used source was a KrF eximer laser (248 nm, 25 ns, 2 J ⁄cm2). Different experimental techniques have been carried out to analyze the fabricated films: the X-ray diffraction (XRD), atomic force microscopy (AFM), Rutherford Backscattering spectrometry (RBS), UV-visible spectrophotometry, M-lines
spectroscopy and Hall effect.
While the ZnO films obtained by the ultrasonic spray technique have been deposited with different deposition times (10, 20, 30 min) on a glass substrate heated at 410 °C, and then they have characterized by XRD, AFM, UV-visible, M-lines and hall effect techniques.
The carried out study shows that all the prepared zinc oxide films have a hexagonal wurtzite-type structure and a preferentially oriented along the direction (002) confused with the c-axis perpendicular to the surface of the substrates. The grain sizes deducted from the XRD measurements vary between 24 and 40 nm. The optical coupling analysis realized by M-lines show that the ZnO films are monomode (for both TE and TM polarizations). However, the undoped ZnO film obtained by PLD is found to be two
guiding modes for TM. The films obtained have an optical transmission of 70 to 90% in the visible region of the spectrum and an optical band gap varying from 3.18 to 3.37 eV.
The electrical conductivity and the concentration of carriers, deduced from Hall effect measurements, are relatively low namely for the films prepared by spray pyrolysis technique.
Diplôme : Doctorat en sciences En ligne : ../theses/physique/TAA6719.pdf Format de la ressource électronique : Permalink : https://bu.umc.edu.dz/md/index.php?lvl=notice_display&id=9904 Exemplaires
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Titre : Etude des propriétés physiques de couches minces TiO2 élaborées par différentes techniques Type de document : texte imprimé Auteurs : Faouzi Hanini, Auteur ; A. Bouabellou, Directeur de thèse Editeur : constantine [Algérie] : Université Constantine 1 Année de publication : 2014 Importance : 115 f. Format : 30 cm. Note générale : 2 copies imprimées disponibles
Langues : Français (fre) Tags : Couche mince TiO2 Dopage Sol-Gel PLD DRX AFM SE.
Thin films Doping XRD ??????? ??????? ????? ??????? ??????? ????????? ??????? ???? ????? ??????Index. décimale : 530 Physique Résumé :
we have undertaken, the main objective optimization of parameters inherent to
both chemical (sol-gel) and physical (Pulsed Laser Deposition) used for the preparation of TiO2 thin films on different substrates. Structural, optical and electrical properties of these films were studied by mean of X-ray diffraction (XRD), atomic force microscopy (AFM), spectroscopic ellipsometry (SE), UV-Visible spectroscopy, and resistivity (conductivity) measurements.
Undoped and Cu-doped TiO2 (Cu:TiO2) thin films were deposited by sol-gel method on glass substrates. Structural, optical and electrical properties of undoped doped copper doped TiO2
films. XRD spectra show that the non-annealed sample is amorphous and crystallized anatase
phase from 400 °C. The obtained films are polycrystalline of anatase structure with (1 0 1) plan as preferential orientation. The surfaces of Cu-doped TiO2 films are smoother than undoped TiO2 films. The optical transmittance of simples is about 75 % in the visible region. The optical band gap undergoes a blue shift from 3.3 to 2.97 eV for undoped and 7at. % Cu doped TiO2 respectively. The values of the refractive index and the packing density increases, with increasing copper doping. The electrical characterization shows a maximum electrical conductivity of 1.29 (Ω cm)-1 obtained for the film doped with 7 at.% Cu.
Al-doped TiO2 (TiO2:Al) thin films were deposited at 450ºC onto glass substrates using pulsed laser deposition method. The used source was a Nd:YAG laser (λ = 335 nm, ν = 5 Hz, Φ = 2 J/cm2 and τ = 8 ns pulse duration). X-rays diffraction spectra showed that the obtained films are
polycrystalline of anatase structure with preferential orientation of (101) direction. AFM images, nanoparticles size and surface roughness mean square values showed that the surfaces of TiO2:Al films are smoother than that of undoped TiO2 films. A blue shift in the absorption edge of TiO2 with increasing Al concentration in the film is noteworthy as it leads to increase in the width of the optical transmission. The optical waveguiding performances of the TiO2:Al films were demonstrated by using the m-lines spectroscopy technique and the results were correlated to the structural properties. Spectroscopic ellipsometry was used to extract the optical constants of the films. The determined band gap of undoped and Al doped films varies from 3.43 to 3.61 eV,which is in accordance to Burstein-Moss shift.Diplôme : Doctorat en sciences En ligne : ../theses/physique/HAN6612.pdf Format de la ressource électronique : Permalink : https://bu.umc.edu.dz/md/index.php?lvl=notice_display&id=9732 Etude des propriétés physiques de couches minces TiO2 élaborées par différentes techniques [texte imprimé] / Faouzi Hanini, Auteur ; A. Bouabellou, Directeur de thèse . - constantine (Route ain el bey, Algérie) : Université Constantine 1, 2014 . - 115 f. ; 30 cm.
2 copies imprimées disponibles
Langues : Français (fre)
Tags : Couche mince TiO2 Dopage Sol-Gel PLD DRX AFM SE.
Thin films Doping XRD ??????? ??????? ????? ??????? ??????? ????????? ??????? ???? ????? ??????Index. décimale : 530 Physique Résumé :
we have undertaken, the main objective optimization of parameters inherent to
both chemical (sol-gel) and physical (Pulsed Laser Deposition) used for the preparation of TiO2 thin films on different substrates. Structural, optical and electrical properties of these films were studied by mean of X-ray diffraction (XRD), atomic force microscopy (AFM), spectroscopic ellipsometry (SE), UV-Visible spectroscopy, and resistivity (conductivity) measurements.
Undoped and Cu-doped TiO2 (Cu:TiO2) thin films were deposited by sol-gel method on glass substrates. Structural, optical and electrical properties of undoped doped copper doped TiO2
films. XRD spectra show that the non-annealed sample is amorphous and crystallized anatase
phase from 400 °C. The obtained films are polycrystalline of anatase structure with (1 0 1) plan as preferential orientation. The surfaces of Cu-doped TiO2 films are smoother than undoped TiO2 films. The optical transmittance of simples is about 75 % in the visible region. The optical band gap undergoes a blue shift from 3.3 to 2.97 eV for undoped and 7at. % Cu doped TiO2 respectively. The values of the refractive index and the packing density increases, with increasing copper doping. The electrical characterization shows a maximum electrical conductivity of 1.29 (Ω cm)-1 obtained for the film doped with 7 at.% Cu.
Al-doped TiO2 (TiO2:Al) thin films were deposited at 450ºC onto glass substrates using pulsed laser deposition method. The used source was a Nd:YAG laser (λ = 335 nm, ν = 5 Hz, Φ = 2 J/cm2 and τ = 8 ns pulse duration). X-rays diffraction spectra showed that the obtained films are
polycrystalline of anatase structure with preferential orientation of (101) direction. AFM images, nanoparticles size and surface roughness mean square values showed that the surfaces of TiO2:Al films are smoother than that of undoped TiO2 films. A blue shift in the absorption edge of TiO2 with increasing Al concentration in the film is noteworthy as it leads to increase in the width of the optical transmission. The optical waveguiding performances of the TiO2:Al films were demonstrated by using the m-lines spectroscopy technique and the results were correlated to the structural properties. Spectroscopic ellipsometry was used to extract the optical constants of the films. The determined band gap of undoped and Al doped films varies from 3.43 to 3.61 eV,which is in accordance to Burstein-Moss shift.Diplôme : Doctorat en sciences En ligne : ../theses/physique/HAN6612.pdf Format de la ressource électronique : Permalink : https://bu.umc.edu.dz/md/index.php?lvl=notice_display&id=9732 Exemplaires
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