Nanolithography Technology In The Nano-photonic Crystals, Metamaterials And Biological Applications

Nanotechnology is a new brand of interdisciplinary scientific research field that has gradually but quickly developed since the late 1980s. It consists of the theoretical and experimental study of different research fields such as nano-electronics, nano-optics, nano-material, NEMS (nano-electro-mechanical systems) and nano-biology. This study significantly broadens people's understanding towards the world around us and plays an important role in the new round of technological revolution in this era. While nanotechnology is the hot topic in research, nano-fabrication techniques are the methods to take the theory into action. There are two main methods for nano-fabrications. One is the bottom-up method, which utilize the modern chemical assembling technology to build up nanostructures through atom and molecu manipulation. The other is the top-down method, which employ nanolithography for the patterning on different substrates, where the resolution is a critical element.This thesis focuses on the top-down nanofabrication method and the scientific study on different nanostructures fabricated by this method during the work. It studies the high resolution electron beam lithography, nanoimprint lithography, near-field lithography, reversal imprint lithography and relatd nano processes including metallization, lift-off and inspection methods. With the nanodevices fabricated during the work, further experimental studies in nano-optics, nano-biology and nano-material sciences are carried out and promising results are obtained.The study starts with one of the most developed nanolithography methods, e-beam lithography. The working principle of the e-beam lithography system is investigated, and different systems from some famous suppliers are compared. With the comprehensive knowledge os the e-beam system, a characterization study for a new chemically amplified resist (CAR) named UV1116 is carried out with respects of the sensitivity, contrast, resolution and dry etching properties of the resist. The improvement of the resist has been confirmed through comparison with its predecessor UVIII resist, which give rise to a broad application of UV1116 in nanolithography. In the study of combining nanolithography technology with life science and material science, we for the first time employ electron beam irradiation in material surface property engineering. Electron beam is used to irradiate the Young's modulus of the substrate surface and therefore change the micro-environment for the growth of human marrow stem cells, leading to a successful differentiation of the stem cells.Meanwhile, e-beam lithography is also combined with nano-optics. We use e-beam lithography to fabricate nano quasi-crystal structures with different sysmetrical folds. Based on the study of these nano quasi-crystal structures, a new binary-phase annular ring mask structure is designed to achieve infinite-fold quasi-crystal structures. In order to fabricate such unique structure, two different methods with self-aligned nanolithography process are developed to achieve the high accuracy of the structure. The fabricated structure is expected to attain resolution that beyond the diffraction limit.On the other hand, a comprehensive study for the electron beam lithography itself has also been carried out. Process flows and parameters for different e-beam lithography resists are designed and tested respectively. The strctures fabricated are further employed in other nanolithography fields such as nanoimprint lithography and near-field lithography.In nanoimprint lithography, systematical study in the influence of nanoimprint parameters on the imprinted structures are carried out and the optimized nanoimprint parameters are set. With the optimized parameters, nanophotonic crystal structures with both dielectric and metallic chiral elements metamaterial structures are fabricated and subsequent optical measurements are carried out afterwards. It is concluded that the special elements in the photonic crystal structures has unique influence in the distribution field of the diffraction. And the manipulation for polarized light of metamaterial with chiral elements has been confirmed.In the research of near-field lithography, FDTD simulations for the distribution of the light intensity when it shines on and passes throught the lithography mask with different patterns and feature sizes are compared. A new optical nanolithography method is developed, combining near-field lithography and reversal imprint lithography. In this optical nanolithograhy method, the theory of evanescent field is employed for the exposure of resist which is spin coated on the mask plate intead of the substrate. The exposed and developed resist with nano patterns is transferred onto the substrate by reversal imprint lithography. In this way, high resolution nano patterns can be achieved on almost all kinds of substrates with different material and shapes by conventional optical lithography method. What's more, nano patterns on the tip of the opcial fiber are fabricated for the first time in the world. Preliminary optical measurements prove good performance of the fabricated structures on the fiber tip. This new optical nanolithography method is low cost but can achieve high volumn productivity. It has great potential in both lab research and industial mass production fields.The technological and scientific achievements made in this research have built up an integrated study system for nanolithography and opened up a brand new field in nanotechnology and nanoscience. The results can be used as a foundation for the nanoscience research in Fudan University in this field and be provided as support and basis for a thorough research in the future.