| With the development of machining technique, femtosecond laser has been applied in many fields, such as chemistry, biomedicine, microelectronic, optical communication, optical information and fine machining. There are several signifi-cant developments in studying the dynamic process of chemistry reaction, control-ling and machining biologic cells, fabrication of lab-on-a-chip and functional mi-crostructures, and optical holographic storage. In this thesis, we have induced one-dimensional, two-dimensional and self-organized periodic structures by fem-tosecond laser, and we also analysed the possible mechanisms. The detail items are as follows:Firstly, we fabricated M shaped gratings on silica glass by the interference of three coplanar replicas of a single femtosecond laser pulse, the as-fabricated struc-tures is resulted from the intensity distribution of three interfered beams, which is consistent with the simulated result. We also studied the influence of prepulse on the encoded gratings by two beams interference, we found that the modulation depth decreases with the increased delay time, and then keep steady. We believe that the prepulse could generate electrons by combined action of multi-photon ionization and avalanche ionization when it impinges on the glass, and the subse-quent pulse will direct multiplication electrons in the irradiated region. Therefore, the prepulse can increase the intensity of femtosecond laser machining materials, and decreasing the threshold of the materials.Secondly, we fabricated two-dimensional periodic structures by the interfer-ence of three non-coplanar beams originating from a single femtosecond laser pulse. The as-formed two-dimensional structure is hexagon lattice. We have deduced the period of hexagon lattice in theory, and studied the changing of the period and elongate ratio with the colliding angles of the three beams and the angles difference. Moreover, when increasing the pulse energy, we observed hat holes and scratch marks in the irradiated region, we believe that the outward releasing of strong shock wave induced scratch marks, while the inward releasing of shock wave induced melting and phase exploding, then the sputtered and melted materials deposited in the scratch marks, forming the hat holes. Thirdly, we fabricated self-organized period structures on ZF6 glass by irradi-ating multi pulses on a focus spot. We observed the structures with orientations parallel and perpendicular to laser polarization are both formed on ZF6 glass. The structure parallel to laser polarization distributes in a pit in the center of irradiation region, and the period increases with increasing pulses number and pulse energy. However, the structure perpendicular to laser polarization distributes around the pit, and the period almost keeps constant with increased pulses number and pulse en-ergy. The self-organization convection rolls and Coulomb explosion induced sur-face reorganization are presented to explain the formation of above structures.Fourthly, we fabricated large-scale uniform gratings on ZF6 glass by dot-by-dot scanning. The SEM and AFM results show that the uniformity of the grating is largely determined by the pulses number, neighboring dots intervals, and pulse energy, while the period of the grating is independent of above three factors. We proposed a model to explain the influence of pulse energy, pulse number and nerghboring dots interval on the fabrication of large scale uniform grating.Last, we fabricated ripples and nanoparticles on silicon by irradiating of fem-tosecond laser. The period of the as-formed ripples is lower than the incident wave-length and decreases with the increasing pulse number. The interference of laser with surface plasmons is proposed to explain the formation of the ripples. The de-creasing of surface ripples is due to the decrease of the surface plasmon wavelength with the decreasing electron number density in the plasma, while the as-formed nanoparticles and debris can be explained by shock wave theory.
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