Titre :	Studies of the thermal stability of the tungsten silicide at different temperatures
Type de document :	document électronique
Auteurs :	Ayoub Henchour, Auteur ; Achour Derafa, Directeur de thèse
Editeur :	Setif:UFA
Année de publication :	2024
Importance :	1 vol (57 f.)
Format :	29 cm
Langues :	Anglais (eng)
Catégories :	Thèses & Mémoires:Physique
Mots-clés :	Silicide Tungsten RTA DRX FPP WSi2 MoSi2
Index. décimale :	530 - Physique
Résumé :	In this work we studied the thermal stability and formation of tungsten silicides, produced by sputtering (PVD) on a Si(100) silicon substrate. We used rapid thermal annealing throughout the study, due to its effective effect (600°C, 800°C, 900°C) on the formation of silicides. During this study, the emphasis is placed on the effects of oxygen and the effects of template and also the effect of temperature on the formation of silicides. Then characterized by X-ray diffraction (XRD ). The main results can be summarized as follows: Oxygen has an effective effect in delaying the formation of silicides and oxygen favors the β-W structure. The effect of the template played an important role in accelerating the reaction, and a distinctive (W-Mo)3Si phase appeared at low temperature. We observed that the hexagonal phase is formed at 600°C, after raising the temperature to 800°C, we notice a complete change in the structure from hexagonal to tetragonal, this explains that the hexagonal structure is unstable when the temperature is raised, unlike the tetragonal structure.
Note de contenu :	Sommaire II. INTRODUCTION ............................................................................ 1 III. Chapter â… : Bibliographic Studies .................................................. 3 A. Silicidation during metal/silicon contact: ....................................... 3 1. Definition of silicide: ................................................................... 3 2. Purpose of silicidation: ............................................................... 4 3. Classification of Silicides:........................................................... 4 B. General information on reactive diffusion: ...................................... 5 1. Review of diffusion: .................................................................... 5 2. Diffusion mechanisms:............................................................... 5 3. Fick’s equations (Fick’s Laws): .................................................... 5 C. Silicide growth by reactive diffusion: ........................................... 7 1. Single phase growth: .................................................................. 7 2. Germination: .............................................................................. 8 3. The lateral Growth: ................................................................... 10 4. Normal Growth: ....................................................................... 11 D. Overview of tungsten silicide thin film formation: ....................... 13 1. W-Si Phase diagram: ................................................................ 13 2. Crystallographic properties of W-Si: .......................................... 14 3. Formation of W/Si: ................................................................... 15 4. Applications of W/Si: ................................................................ 15 5. The importance of tungsten silicides in transistors : ................... 16 IV. Chapter â…¡: Experimental techniques used. ................................... 18 A . Technique for producing thin layers: ............................................. 18 1. Principle of Sputtering : ............................................................ 18 2. Preparation of substrates :........................................................ 19 3. Sample deposits : .................................................................... 19 4. Rapid thermal annealing : ......................................................... 20 B. Characterization techniques : ...................................................... 22 1. X-ray diffraction (XRD) :............................................................. 22 2. Atomic force microscopy (AFM) : ............................................... 24 3. The four-point Probe Method (FPP): ........................................... 26 V. Chapter â…¢: Results and discussions. ........................................... 29 A. Microstructural characterizations by X-ray diffraction: .................. 29 1. Oxide effect on the formation of silicide: ................................... 30 2. Effect of alloying elements W1-xMox/Si(100) on formation of silicide: 34 3. Temperature effect on formation of silicide: .............................. 40 VI. References ................................................................................. 48
Côte titre :	MAPH/0644

Studies of the thermal stability of the tungsten silicide at different temperatures [document électronique] / Ayoub Henchour, Auteur ; Achour Derafa, Directeur de thèse . - [S.l.] : Setif:UFA, 2024 . - 1 vol (57 f.) ; 29 cm.
Langues : Anglais (eng)

Catégories :	Thèses & Mémoires:Physique
Mots-clés :	Silicide Tungsten RTA DRX FPP WSi2 MoSi2
Index. décimale :	530 - Physique
Résumé :	In this work we studied the thermal stability and formation of tungsten silicides, produced by sputtering (PVD) on a Si(100) silicon substrate. We used rapid thermal annealing throughout the study, due to its effective effect (600°C, 800°C, 900°C) on the formation of silicides. During this study, the emphasis is placed on the effects of oxygen and the effects of template and also the effect of temperature on the formation of silicides. Then characterized by X-ray diffraction (XRD ). The main results can be summarized as follows: Oxygen has an effective effect in delaying the formation of silicides and oxygen favors the β-W structure. The effect of the template played an important role in accelerating the reaction, and a distinctive (W-Mo)3Si phase appeared at low temperature. We observed that the hexagonal phase is formed at 600°C, after raising the temperature to 800°C, we notice a complete change in the structure from hexagonal to tetragonal, this explains that the hexagonal structure is unstable when the temperature is raised, unlike the tetragonal structure.
Note de contenu :	Sommaire II. INTRODUCTION ............................................................................ 1 III. Chapter â… : Bibliographic Studies .................................................. 3 A. Silicidation during metal/silicon contact: ....................................... 3 1. Definition of silicide: ................................................................... 3 2. Purpose of silicidation: ............................................................... 4 3. Classification of Silicides:........................................................... 4 B. General information on reactive diffusion: ...................................... 5 1. Review of diffusion: .................................................................... 5 2. Diffusion mechanisms:............................................................... 5 3. Fick’s equations (Fick’s Laws): .................................................... 5 C. Silicide growth by reactive diffusion: ........................................... 7 1. Single phase growth: .................................................................. 7 2. Germination: .............................................................................. 8 3. The lateral Growth: ................................................................... 10 4. Normal Growth: ....................................................................... 11 D. Overview of tungsten silicide thin film formation: ....................... 13 1. W-Si Phase diagram: ................................................................ 13 2. Crystallographic properties of W-Si: .......................................... 14 3. Formation of W/Si: ................................................................... 15 4. Applications of W/Si: ................................................................ 15 5. The importance of tungsten silicides in transistors : ................... 16 IV. Chapter â…¡: Experimental techniques used. ................................... 18 A . Technique for producing thin layers: ............................................. 18 1. Principle of Sputtering : ............................................................ 18 2. Preparation of substrates :........................................................ 19 3. Sample deposits : .................................................................... 19 4. Rapid thermal annealing : ......................................................... 20 B. Characterization techniques : ...................................................... 22 1. X-ray diffraction (XRD) :............................................................. 22 2. Atomic force microscopy (AFM) : ............................................... 24 3. The four-point Probe Method (FPP): ........................................... 26 V. Chapter â…¢: Results and discussions. ........................................... 29 A. Microstructural characterizations by X-ray diffraction: .................. 29 1. Oxide effect on the formation of silicide: ................................... 30 2. Effect of alloying elements W1-xMox/Si(100) on formation of silicide: 34 3. Temperature effect on formation of silicide: .............................. 40 VI. References ................................................................................. 48
Côte titre :	MAPH/0644