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Partager le résultat de cette recherche Interroger des sources externesCaractérisations des réactions interfaciales dans les couches minces métalliques binaires et multiples / Farida Kezai (Née Medjani)
Titre : Caractérisations des réactions interfaciales dans les couches minces métalliques binaires et multiples Type de document : texte imprimé Auteurs : Farida Kezai (Née Medjani) ; Univ. de Constantine, Éditeur scientifique ; Rachid Halimi, Directeur de thèse Année de publication : 2007 Importance : 89 f. Note générale : 01 Disponible à la salle de recherche 02 Disponibles au magazin de la B.U.C. 01 CD Langues : Français (fre) Catégories : Français - Anglais
PhysiqueTags : Pulvérisation Morphologie Multicouches TiN/AlN Nanocomposite Propriétés structurales Résistivité électrique Nanodureté Sputtering Multilayers TiN/AlN Zr-Si-N Structural proprieties Morphology Electrical resistivity Nanohardness Index. décimale : 530 Physique Résumé : DC reactive magnetron co-sputtering was used for the deposition of Zr-Si-N thin films and a multilayers TiN/AlN.
Si content (CSi) was varied by changing the power applied on the Si target, whereas that on Zr target was kept constant. Four series of samples have been deposited at various substrate temperatures: room temperature, 240 °C, 440 °C and 640 °C. The evolution of morphology,
crystalline structure, grain size and lattice constant has been investigated by X-ray diffraction analyses. Nanohardness, stress and resistivity measurements provide complementary information, which validate the proposed 3-step model for the film formation of the Zr-Si-N system deposited by reactive magnetron cosputtering. For low Si content the Si atoms substitute the Zr atoms in the ZrN lattice. Above the solubility limit, a nanocomposite film containing ZrN:Si nanocrystallites and amorphous SiNy is formed. Further increase of Si content results in a reduction of grain size (D), while the thickness of the SiNy layer at the crystallite surface remains constant. The increasing amount of the SiNy amorphous phase in the films is realized by increasing the surface to volume ratio of the crystallites. In this concentration range, the size of the crystallites in the Zr-Si-N films decreases according to the relationship CSi ~1/D. With
increasing the substrate temperature, the solubility limit of Si in ZrN decreases whereas the films’ global nitruration (CN /(CSi + CZr)) increases. The concentration dependence of the electrical resistivity is interpreted in terms of the variation of the SiNy layer thickness.
By controlling the thickness of individual layers (1-50 nm) and substrate bias (Vb = -25 V and V b = - 100V) two series of samples were prepared. The films were characterized using X-ray diffraction (DRX), cross-sectional electron microscopy (MET) and nanoindentation. The
measured hardness of multilayer films were found to be always higher than the rule of the mixture, but the magnitude of hardness enhancement was found to be dependent on the bilayer thickness and bias substrate. Decreasing progressively the layer thickness favors the alignment of
(0002) basal plan of w-AlN on (111) plane of TiN, and results in the development of strong (111) texture, prerequisite for stabilization of c-AlN and formation of epitaxial coherent structures.Diplôme : Doctorat En ligne : ../theses/physique/KEZ5008.pdf Permalink : index.php?lvl=notice_display&id=3347 Caractérisations des réactions interfaciales dans les couches minces métalliques binaires et multiples [texte imprimé] / Farida Kezai (Née Medjani) ; Univ. de Constantine, Éditeur scientifique ; Rachid Halimi, Directeur de thèse . - 2007 . - 89 f.
01 Disponible à la salle de recherche 02 Disponibles au magazin de la B.U.C. 01 CD
Langues : Français (fre)
Catégories : Français - Anglais
PhysiqueTags : Pulvérisation Morphologie Multicouches TiN/AlN Nanocomposite Propriétés structurales Résistivité électrique Nanodureté Sputtering Multilayers TiN/AlN Zr-Si-N Structural proprieties Morphology Electrical resistivity Nanohardness Index. décimale : 530 Physique Résumé : DC reactive magnetron co-sputtering was used for the deposition of Zr-Si-N thin films and a multilayers TiN/AlN.
Si content (CSi) was varied by changing the power applied on the Si target, whereas that on Zr target was kept constant. Four series of samples have been deposited at various substrate temperatures: room temperature, 240 °C, 440 °C and 640 °C. The evolution of morphology,
crystalline structure, grain size and lattice constant has been investigated by X-ray diffraction analyses. Nanohardness, stress and resistivity measurements provide complementary information, which validate the proposed 3-step model for the film formation of the Zr-Si-N system deposited by reactive magnetron cosputtering. For low Si content the Si atoms substitute the Zr atoms in the ZrN lattice. Above the solubility limit, a nanocomposite film containing ZrN:Si nanocrystallites and amorphous SiNy is formed. Further increase of Si content results in a reduction of grain size (D), while the thickness of the SiNy layer at the crystallite surface remains constant. The increasing amount of the SiNy amorphous phase in the films is realized by increasing the surface to volume ratio of the crystallites. In this concentration range, the size of the crystallites in the Zr-Si-N films decreases according to the relationship CSi ~1/D. With
increasing the substrate temperature, the solubility limit of Si in ZrN decreases whereas the films’ global nitruration (CN /(CSi + CZr)) increases. The concentration dependence of the electrical resistivity is interpreted in terms of the variation of the SiNy layer thickness.
By controlling the thickness of individual layers (1-50 nm) and substrate bias (Vb = -25 V and V b = - 100V) two series of samples were prepared. The films were characterized using X-ray diffraction (DRX), cross-sectional electron microscopy (MET) and nanoindentation. The
measured hardness of multilayer films were found to be always higher than the rule of the mixture, but the magnitude of hardness enhancement was found to be dependent on the bilayer thickness and bias substrate. Decreasing progressively the layer thickness favors the alignment of
(0002) basal plan of w-AlN on (111) plane of TiN, and results in the development of strong (111) texture, prerequisite for stabilization of c-AlN and formation of epitaxial coherent structures.Diplôme : Doctorat En ligne : ../theses/physique/KEZ5008.pdf Permalink : index.php?lvl=notice_display&id=3347 Exemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité KEZ/5008 KEZ/5008 Thèse Bibliothèque principale Thèses Disponible
Titre : Contribution à l'élaboration de couches minces d'oxydes transparents conducteurs (TCO). Type de document : texte imprimé Auteurs : Fayssal Ynineb, Auteur ; N. Attaf, Directeur de thèse Mention d'édition : 16/05/2010 Editeur : Constantine : Université Mentouri Constantine Année de publication : 2010 Importance : 104 f. Format : 30 cm. Note générale : 01 Disponible à la salle de recherche 01 Disponible au magazin de la B.U.C. 01 CD Langues : Français (fre) Catégories : Français - Anglais
PhysiqueTags : Sciences des matériaux: Semi-conducteurs DRX Résistivité électrique Couches minces TCO Spray ultrasonique Caractérisation optique Thin films TCO Ultrasonic spray Optical characterization Electrical resistivity الشرائح الرقیقة الرش فوق الصوتي الوصف الضوئي المقاومیة الكھربائیة Index. décimale : 530 Physique Résumé : Our work concerns the development and the characterization of the conducting transparent oxides thin films of: ZnO, SnO2 and In2O3, and their mixtures by the ultrasonic technique spray at 300°C.
In the first part of this thesis, we realized, in addition to pure oxides, a series of deposit containing ZnO by using the mixtures of: [ZnO:SnO2]
and [ZnO:In2O3]. In the second part, we realized another serie of oxides [SnO2:In2O3]. In the two parts we studied the influence of the rate mixture of components on the characteristics of films. These films are analyzed by various characterization techniques of materials. The structural characterization of films by analysis of the spectra of X-ray diffraction showed that the films based on the mixtures and containing ZnO present a preferential direction according to the plan (002) for the Rb1 series and (100) for the Rb2 series. In films of the series [SnO2:In2O3] the preferential orientation is along the axis (222) of In2O3. The UV-Visible spectrophotometer of these films confirms that it is possible to obtain good transparent films of TCO with a transmittance of about 75 to 85% in the visible range. The measurement of electric resistivity also confirmed the decrease of the electrical resistivity with mixtures to a value of 10-3 (Ω.cm).Note de contenu : Annexes. Diplôme : Magistère En ligne : ../theses/physique/YNI5646.pdf Format de la ressource électronique : Permalink : index.php?lvl=notice_display&id=3397 Contribution à l'élaboration de couches minces d'oxydes transparents conducteurs (TCO). [texte imprimé] / Fayssal Ynineb, Auteur ; N. Attaf, Directeur de thèse . - 16/05/2010 . - Constantine : Université Mentouri Constantine, 2010 . - 104 f. ; 30 cm.
01 Disponible à la salle de recherche 01 Disponible au magazin de la B.U.C. 01 CD
Langues : Français (fre)
Catégories : Français - Anglais
PhysiqueTags : Sciences des matériaux: Semi-conducteurs DRX Résistivité électrique Couches minces TCO Spray ultrasonique Caractérisation optique Thin films TCO Ultrasonic spray Optical characterization Electrical resistivity الشرائح الرقیقة الرش فوق الصوتي الوصف الضوئي المقاومیة الكھربائیة Index. décimale : 530 Physique Résumé : Our work concerns the development and the characterization of the conducting transparent oxides thin films of: ZnO, SnO2 and In2O3, and their mixtures by the ultrasonic technique spray at 300°C.
In the first part of this thesis, we realized, in addition to pure oxides, a series of deposit containing ZnO by using the mixtures of: [ZnO:SnO2]
and [ZnO:In2O3]. In the second part, we realized another serie of oxides [SnO2:In2O3]. In the two parts we studied the influence of the rate mixture of components on the characteristics of films. These films are analyzed by various characterization techniques of materials. The structural characterization of films by analysis of the spectra of X-ray diffraction showed that the films based on the mixtures and containing ZnO present a preferential direction according to the plan (002) for the Rb1 series and (100) for the Rb2 series. In films of the series [SnO2:In2O3] the preferential orientation is along the axis (222) of In2O3. The UV-Visible spectrophotometer of these films confirms that it is possible to obtain good transparent films of TCO with a transmittance of about 75 to 85% in the visible range. The measurement of electric resistivity also confirmed the decrease of the electrical resistivity with mixtures to a value of 10-3 (Ω.cm).Note de contenu : Annexes. Diplôme : Magistère En ligne : ../theses/physique/YNI5646.pdf Format de la ressource électronique : Permalink : index.php?lvl=notice_display&id=3397 Exemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité YNI/5646 YNI/5646 Thèse Bibliothèque principale Thèses Disponible
Titre : Etude des propriétés physiques des céramiques supraconductrices dopées : YBa2Cu3O7-δ. Type de document : texte imprimé Auteurs : Souheila Chamekhi, Auteur ; Abderaheman Bouabellou, Directeur de thèse Editeur : جامعة الإخوة منتوري قسنطينة Année de publication : 2019 Importance : 102 f. Format : 30 cm. Note générale : 2 copies imprimées disponibles
Langues : Français (fre) Catégories : Français - Anglais
PhysiqueTags : physique:Sciences des Matériaux SHTC YBCO Dopage DRX MEB Spectroscopie Raman Résistivité électrique Susceptibilité magnétique HTCS Doping XRD SEM Raman spectroscopy Electrical resistivity Magnetic Susceptibility الموصلات الفائقة الناقلية ذات الدرجة الحرجة العالية التمغنط الانعراج السيني المجهر الالكتروني أطياف Rama Index. décimale : 530 Physique Résumé : In order to study the effect of doping on the physical properties of superconducting YBa2Cu3O7-δ ceramic compound in which Cu was substituted by: Ni, Ag, Mn and Co. We have prepared our samples from carbonate BaCO3, oxides Y2O3, CuO, MnO2 and CoO and AgNO3, by the solid state reaction method. The samples were then characterized by beams of the techniques of X-ray diffraction (XRD), scanning electron microscopy (SEM), X-ray energy dispersive (EDX) analysis, Raman spectroscopy, electrical resistivity and DC susceptibility measurements. The analysis of the XRD shows the presence of the orthorhombic major phase YBa2Cu3O7-δ (YBCO) and the secondary phases BaCuO2 (Y011) and Y2BaCuO5 (Y211). No phase transition occurred at the atomic concentration dopants 0 x 4%. The refinement by Winplotr and Dicvol04 programs shows that the cell parameters have been affected, due to the incorporation of the dopant into the cell. The SEM micrographs show that the incorporation of all the dopants induces in generally a thinner grain with a porous structure, except for some samples that have large grains. The EDX analysis confirms the incorporation of the dopants into the grains. This analysis reveals also that the distribution dopants in the samples is not homogenous. These analyses allow to suggest the possibility of substitution of Ag and Mn in barium sites and copper chain sites Cu(1). Measurements of DC magnetic susceptibility and electrical resistivity reveal a decrease in TCon as a function of the doping rate. This decrease is more probably due to the change in carrier density, CuO2 plane disorder and overall oxygen content, for nickel and manganese. This is not the case for the silver doped sample with 0.5 at.% which has a greater TC than the pure sample. The results of the Raman spectroscopy confirm the presence of the YBCO phase with the two secondary Y011 and Y211 phases. The incorporation of the dopant in the grains in the Cu (2) planar sites, and the contraction of the parameter c. The recorded five active modes confirm that the structure is orthorhombic for all the samples and the phase transition has not take place in the interval 0 x 4%. Diplôme : Doctorat en sciences En ligne : ../theses/physique/CHA7504.pdf Format de la ressource électronique : Permalink : index.php?lvl=notice_display&id=11337 Etude des propriétés physiques des céramiques supraconductrices dopées : YBa2Cu3O7-δ. [texte imprimé] / Souheila Chamekhi, Auteur ; Abderaheman Bouabellou, Directeur de thèse . - جامعة الإخوة منتوري قسنطينة, 2019 . - 102 f. ; 30 cm.
2 copies imprimées disponibles
Langues : Français (fre)
Catégories : Français - Anglais
PhysiqueTags : physique:Sciences des Matériaux SHTC YBCO Dopage DRX MEB Spectroscopie Raman Résistivité électrique Susceptibilité magnétique HTCS Doping XRD SEM Raman spectroscopy Electrical resistivity Magnetic Susceptibility الموصلات الفائقة الناقلية ذات الدرجة الحرجة العالية التمغنط الانعراج السيني المجهر الالكتروني أطياف Rama Index. décimale : 530 Physique Résumé : In order to study the effect of doping on the physical properties of superconducting YBa2Cu3O7-δ ceramic compound in which Cu was substituted by: Ni, Ag, Mn and Co. We have prepared our samples from carbonate BaCO3, oxides Y2O3, CuO, MnO2 and CoO and AgNO3, by the solid state reaction method. The samples were then characterized by beams of the techniques of X-ray diffraction (XRD), scanning electron microscopy (SEM), X-ray energy dispersive (EDX) analysis, Raman spectroscopy, electrical resistivity and DC susceptibility measurements. The analysis of the XRD shows the presence of the orthorhombic major phase YBa2Cu3O7-δ (YBCO) and the secondary phases BaCuO2 (Y011) and Y2BaCuO5 (Y211). No phase transition occurred at the atomic concentration dopants 0 x 4%. The refinement by Winplotr and Dicvol04 programs shows that the cell parameters have been affected, due to the incorporation of the dopant into the cell. The SEM micrographs show that the incorporation of all the dopants induces in generally a thinner grain with a porous structure, except for some samples that have large grains. The EDX analysis confirms the incorporation of the dopants into the grains. This analysis reveals also that the distribution dopants in the samples is not homogenous. These analyses allow to suggest the possibility of substitution of Ag and Mn in barium sites and copper chain sites Cu(1). Measurements of DC magnetic susceptibility and electrical resistivity reveal a decrease in TCon as a function of the doping rate. This decrease is more probably due to the change in carrier density, CuO2 plane disorder and overall oxygen content, for nickel and manganese. This is not the case for the silver doped sample with 0.5 at.% which has a greater TC than the pure sample. The results of the Raman spectroscopy confirm the presence of the YBCO phase with the two secondary Y011 and Y211 phases. The incorporation of the dopant in the grains in the Cu (2) planar sites, and the contraction of the parameter c. The recorded five active modes confirm that the structure is orthorhombic for all the samples and the phase transition has not take place in the interval 0 x 4%. Diplôme : Doctorat en sciences En ligne : ../theses/physique/CHA7504.pdf Format de la ressource électronique : Permalink : index.php?lvl=notice_display&id=11337 Exemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité CHA/7504 CHA/7504 Thèse Bibliothèque principale Thèses Disponible
