Elaboration par des procédés assistés plasma microonde et caractérisations physico-chimiques de couches minces de matériaux composites cuivre/carbone nanostructurés pour applications tribologiques

L'objectif de ce travail est d'obtenir des couches composées d'une matrice de carbone amorphe hydrogéné (a-C:H) enveloppant des grains de cuivre cristallisé de taille nanométrique, et d'étudier les propriétés mécaniques et tribologiques de ce matériau nouveau. L'équipement de dépôt utilisé est un réacteur plasma micro-onde. Les couches ont été obtenues à partir de deux mélanges gazeux distincts : argon-méthane et argon-acétylène, et d'une cible de cuivre polarisée. L'étude de la composition et de la structure des couches a révélé un saut d'incorporation du carbone ainsi qu'une auto-organisation en couches du cuivre et du carbone pour certains paramètres de dépôt. Les propriétés mécaniques et tribologiques observées ont mis en évidence un comportement mécanique original, et confirment le rôle de l'inclusion de nanoparticules dans le renforcement des propriétés mécaniques du carbone amorphe hydrogéné.GRENOBLE1-BU Sciences (384212103) / SudocSudocFranceF

COUCHES MINCES DE FLUORURE DE MAGNESIUM DEPOSEES PAR PROCEDES D'EVAPORATION POUR APPLICATIONS OPTIQUES

GRENOBLE1-BU Sciences (384212103) / SudocSudocFranceF

Selective Chemical Vapor Deposition

Selective area deposition has received much attention in IC technology in the past forty years. Its advantage in IC technology is that one saves a mask and a full sequence of lithography, etching, resist removal and cleaning. In Selective Chemical Vapor Deposition (CVD) the selectivity is obtained by the different chemical behavior of reactants with different surfaces. The advantage of selective CVD is the self-alignment with respect to the previous pattern, which allows for tight design-rules in this phase of the IC production. Selective epitaxial Silicon deposition was investigated in the sixties of the last century. Later selective Tungsten, selective epitaxial SiGe, selective IH-V and II-VI compounds and recently selective deposition of Copper became intensively researched subjects. In these cases of selective deposition one etches a window in a dielectric to the substrate and then deposits the required layer. Due to nucleation matters it starts to grow immediately on the substrate material whereas the nucleation on the dielectric is retarded. However, in nature one never gets advantages for free. Selectivity loss, reaction with the substrate material, facetting, lateral overgrowth on the dielectric and pattern-density dependency are major problems

Localized Laser-Assisted Deposition of Silicon,Silicon Nitride and Silicon Dioxide

ABSTRACT The localized laser-induced deposition of an insulator for silicon-based microelectronics seems to be an unsolved problem. In order to understand the limiting mechanism in the deposition, the formation kinetics of silicon, silicon oxide and silicon nitride using various laser wavelengths and gas mixtures have been studied Depending upon wavelength and laser-induced temperature, various chemical reactions are involved. In the presence of ammonia, the growth rate of silicon nitride dots was found to be lower than the corresponding silicon deposition rate, indicating that deposition starts with silane decomposition followed by nitridation of silicon. By evaluating the influence of the wavelengths, the existence of a photolytic aided reaction is detected in the presence of 2.4 eV photons. In the presence of oxygen molecules and under most experimental conditions, no deposition occurs. The formation of volatile intermediate compounds can explain the difficulty of locally depositing silicon dioxide

Kinetics of Laser-Assisted Chemical Vapor Deposition of Tungsten Microstructures

Tungsten microstructures (dots, strips and films) have been deposited via H 2 reduction of WF 6 on polycrystalline silicon-coated quartz substrates irradiated with a focused cw argon laser beam. The deposition rate of W dots, deduced from α-step measurements of the height of dots, was investigated as a function of irradiation time, composition of H 2 -WF 6 gas mixtures and laser-induced surface temperature. At a laser-induced surface temperature ranging from 340° to 670°C with an H 2 partial pressure varying from 50 to 700 Torr, the reaction order with respect to H 2 was equal to one-half, whereas at higher temperatures (750°-950°C) and lower H 2 partial pressures (20-80 Torr), the reaction order with respect to H 2 was found to be one. The reaction mechanism of the H 2 reduction of WF 6 on substrates irradiated with the argon laser beam is discussed

PROCESS FOR LOCALIZED ENGRAVING OF A SILICON OXIDE LAYER

The process involves stages in which the substrate carrying the SiO2 layer is placed in a vessel at a pressure below about 10 Pa in the presence of SiH4. The zone to be etched is heated locally, preferably with a focused laser beam. Application to the opening-up of silicon oxide layers on the surface of semiconductor components during manufacture

Phase Composition and Tribological Properties of Copper/Carbon Composite Films.

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