Femtosecond Laser Direct Writing (FLDW) is a viable technique for producing photonic devices in bulk materials. This novel manufacturing technique is versatile due to its full 3D fabrication capability. Typically, the only requirement for this process is that the base material must be transparent to the laser wavelength. The modification process itself is based on non-linear energy absorption of laser light within the focal volume of the incident beam. This thesis addresses the feasibility of this technique for introducing photonic structures into novel dielectric materials. Additionally, this work provides a deeper understanding of the lightmatter interaction mechanism occurring at high pulse repetition rates. A novel structure on the sample surface in the form of nano-fibers was observed when the bulk material was irradiated with high repetition rate pulse trains. To utilize the advantages of the FLDW technique even further, a transfer of the technology from dielectric to semiconductor materials is investigated. However, this demands detailed insight of the absorption and modification processes themselves. Experiments and the results suggested that non-linear absorption, specifically avalanche ionization, is the limiting factor inhibiting the application of FLDW to bulk semiconductors with today’s laser sources.

La technique d’usinage par impulsions laser femtosecondes possède de nombreux avantages du fait des spécificités physique de l’interaction laser/matière en mode ultra-bref et est donc susceptible d’intéresser le monde industriel. Néanmoins elle présente aussi certaines limitations, principalement en terme de flexibilité et de productivité, limitant l’accès à ce marché. Pour repousser ces limites, nous proposons d’adjoindre des techniques de contrôle du faisceau, à la fois en taille, et plus généralement en forme, exploités par ailleurs dans d’autres domaines scientifiques (pincettes optiques notamment). Ces techniques reposent sur l’utilisation de modulateurs spatiaux de lumière (SLM). Deux solutions sont proposées : la modulation d’amplitude en configuration d’imagerie, et la modulation de phase pure en configuration de Fourier. Le formalisme, les différentes problématiques et la mise en oeuvre de ces deux techniques au sein d’une station de travail prototype que nous avons développée sont présentés. Enfin, nous mettons en évidence le gain apporté par ces techniques sur des problématiques concrètes, tels que l’usinage de réseaux résonant à l’échelle nanométrique, la réduction du temps d’usinage de ces réseaux (ou d’autres motifs), et l’amélioration de la qualité d’usinage de rainures / Femtosecond laser machining processes present many interesting properties owing to the specificities of the light/matter interaction in ultrafast regime. Thus the process may be of prime interest in industrial applications. However some aspects are not compatible with industrialization: namely a lack of flexibility and productivity. To overcome this limitations we propose to add beam shaping techniques in the process that allow control of the beam both in size and shape. These techniques are based on Spatial Light Modulators (SLM). Two different solutions are proposed: amplitude modulation in a geometrical conjugation scheme, and pure phase modulation in a Fourier scheme. Both are integrated in a prototype workstation. We justify the different choices made during the development by the analysis of the formalisms and specific problematics. Finally, enhancements of the femtosecond laser machining process are practically demonstrated in three different fields: reducing the resolution to nanometric scale, reducing the processing time of different texturations and enhancing the quality of simple grooves by modifying only the beam shape

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