Fabrication of Functional 3D Micro/Nanostructures by Laser Multiphoton Polymerization Technique ; Trimačių funkcinių mikro- ir nanodarinių formavimas lazerinės daugiafotonės polimerizacijos būdu

Femtosecond Laser Multiphoton Polymerization (FLMP) is a rapid prototyping technique enabling fabrication of 3D microstructures of complex geometry with 100 nm spatial resolution and unmatched flexibility. FLMP is based on nonlinear light and matter interaction - a tightly focused pulsed light beam, having high intensities (~TW/cm2), modifies the photosensitive material within femtoliter volume. After the exposure sample is immersed in the developer bath, the unexposed regions of the material are removed and a free standing 3D micro/nanostructure is revealed on the substrate. Such point-by-point photostructuring enables to directly write functional micro/nanostructures which can be applicable in photonics, microoptics, micromechanics, microfluidics and being transferred to the production of artificial polymeric scaffolds, metamaterials and plasmonic functional devices. In this thesis, experimental results on FLMP 3D micro/nanostructuring of various photopolymers are presented. It starts from the construction and development of the laser fabrication setup. Issues like optimization of the laser structuring parameters for increasing fabrication resolution and production throughput are presented and discussed. Functional micro/nanodevices manufactured out of acrylate, hybrid organic-inorganic and biodegradable photopolymers are demonstrated and their performance is investigated. During the work several problems were solved: 1) Development of novel laboratory setup based on diode pumped solid state femtosecond Yb:KGW amplified laser system combined with high translation speed and precision linear motion stages designed for rapid FLMP micro/nanostructuring over a large area. Various irradiation wavelengths and pulse repetition rates were tested in order to optimize the nonlinear excitation of the photosensitive material. High sample translation speed (increasing from µm/s to mm/s) corresponding to rapid structure writing were applied in order to manufacture micro/nanostructured samples over a large areas (from tens of ...