The Design And Fabrication Of Biomimetic Picoliter/Nanaoliter High-Throughput Sampling System

The objectives of this research are to develop the micro-nanofluidic drive and controlled technology based on the interface effects, improve the overall system level of miniaturization and integration, establish the nanoliter sample skin upgrade new principles and new methods of sampling, make up the biomimetic microfluidic new devices and systems based on polymer. This paper designs a microfluidic injection systems and produces a key part of the injection systems-hollow silicon microneedle.Chapter one briefly introduces the characteristics and application areas of microfluidic chips. Then the development of microneedles is be present. The last one is to describe the major work of this thesis.Combined with the sampling systems of microfluidic chip, chapter two is to design the bionic pena increased fluxinjection systems based on the previous research results. There are design of silicon hollow microneedles, structural design of micro-channel size, high-throughput design andthe design of overall combination. Finally we get the power-driven micro-nano fluidic injection systems used as the injection systems in this study.Chapter three firstly introduces anisotropic wet etching used KOH in the study and then shows the silicon crystal and the formation models of silicon microneedles. The most important thing is that a series experiments were prepared and a large number experiments data of silicon microneedles were got. Through a series of experiments,we investgate various aspects that have effects on the formation of silicon micro-needle during etching.Moreover, the temperature and concentration of etching solution and the concentration of IPA are studied to determine the effects on results of etching and wall-shape of silicon micro-needles. When employing 50%KOH (KOH150g,water150ml) solution in the condition of 87℃water bathing and etching 150min, the silicon microneedles are composed of {411} crystal surface (inclination76.37°,height of 100μm).When employing 40%KOH(KOH100g,water150ml,30gIPA) solution in the condition of 78℃water bathing and etching 240min, the silicon microneedles are composed of {133} crystal surface (inclination46.5°,height of 100μm.Chapter four describes the dry etching technique and inductively coupled plasma etching technology. Then the equipment used in the experiments is introduced. Besides, we design the process of silicon micro-hole production and the mask program. Finally, the experiments are prepared and the process is divided into three stages. There are to explore the experimental techniques, improve the process in the mid-term and determine the final process. Finally we get the silicon microneedles with the vertical wall,25um in diameter,380um in depth. And we analysis the results of the experimental lag effectsThrough this study, the ideal silicon microneedles and silicon micro-tip are got. Besides, a set of process parameters to prepared the hollow microneedles made of silicon is found and this will play an important role in the following study.