微流控芯片金属模具电铸成型技术研究

发布时间：2018-03-18 11:01

本文选题：电铸　切入点：模具　出处：《广东工业大学》2015年硕士论文　论文类型：学位论文

【摘要】：微流控芯片可应用于微检测、药物输送(微型泵,微针)、工业和环境分析装置、制药和生命科学研究、食品检测、新材料制备,市场需求潜力巨大。作为微流控技术的重要载体,微流控芯片是在几平方厘米的芯片上构建化学或生物实验室,具有费用低、效率高、便携性好、准确度高等优点。但目前微流控芯片的产业化成本相对较高,基于热压成型、注塑成型的模具成型工艺是解决微流控芯片大批量制造难题的重要方法,而制造加工出含有大规模微结构的精密微流控芯片模具是该技术的关键所在,电铸作为一种低成本的大面积微结构制造技术,可用于微流控芯片金属模具的制备。结合微流控芯片金属模具加工工艺要求,制定了照相制版技术、化学蚀刻技术和电铸技术相结合的工艺方法。通过对被加工件进行光刻处理来制作掩膜,然后进行化学蚀刻和电铸成型来加工微流控芯片金属模具。化学蚀刻采用喷淋蚀刻机床,电铸实验平台通过PID控制方式来实现对温度的精确控制,阴极工装夹具设计了轨迹式运动,提高电铸铸层的均匀性。围绕电铸工艺,研究了电铸阴极平动、阴极电流密度、掩膜厚度、二次辅助阴极等方面对微流控芯片金属模具电铸成型微结构侧壁陡直度和铸层均匀性的影响。实验设计的含有外加电势二次辅助阴极的三电极电铸体系可以提高铸层的均匀性。针对电铸工艺因素较为复杂的问题,以铸前蚀刻深度、温度、掩膜厚度和阴极电流密度为重点工艺因素,进行正交实验,得到优化的实验工艺方案。研究对比了化学微蚀刻法和微细电铸法制备微流控芯片金属模具。化学微蚀刻法制备的模具微结构侧壁呈不规则弧形、尺寸均匀性相对较差,表面粗糙度较大(Ra3.58μm)。而微细电铸法制备的模具微结构的侧壁呈规则的梯形、尺寸均匀性好、表面粗糙度较低(Ra 0.65 μm)。综合比较,微细电铸法制备的微流控芯片金属模具在微结构的侧壁陡度、尺寸均匀性和粗糙度方面比化学微蚀刻好。采用控制电铸过程电源脉冲频率、脉冲波形的实验方案,进行微流控芯片模具流道表面微纳结构制备的初步工艺研究,较高的频率和一定的脉冲波形可以制备得到具有一定尺寸表面微纳结构的芯片微流道。
[Abstract]:Microfluidic chips can be used for microdetection, drug delivery (micro pumps, microneedles, industrial and environmental analysis devices, pharmaceutical and life sciences research, food testing, preparation of new materials, As an important carrier of microfluidic technology, microfluidic chips are built on several square centimeters of chips to build chemical or biological laboratories, with low cost, high efficiency, good portability. However, the industrialization cost of microfluidic chips is relatively high at present. The molding process based on hot pressing and injection molding is an important method to solve the problem of mass manufacturing of microfluidic chips. The key of this technology is to manufacture and manufacture precision microfluidic chip mould with large scale microstructures. Electroforming is a low cost and large area microstructure manufacturing technology. It can be used in the preparation of metal die for microfluidic chip. According to the process requirements of metal die of microfluidic chip, the photographic plate making technology is established. The process of combining chemical etching with electroforming. Mask is made by photolithography of the workpiece. Then chemical etching and electroforming were carried out to process metal die of microfluidic chip. Spray etching machine was used for chemical etching. The electroforming experiment platform realized precise control of temperature by PID control method. In order to improve the uniformity of electroforming layer, the traverse motion of cathode fixture is designed. The translational motion of cathode, cathode current density and mask thickness are studied around the electroforming process. The influence of secondary auxiliary cathode on the sidewall steepness and uniformity of microstructures in metal die electroforming of microfluidic chip was studied. The experimental design of three-electrode electroforming system with secondary auxiliary cathode with external potential can be improved. Uniformity of the cast layer. For the more complicated factors of electroforming process, The orthogonal experiments were carried out with the emphasis on etching depth, temperature, mask thickness and cathode current density before casting. The optimized experimental process was obtained. The preparation of microfluidic chip metal dies by chemical micro-etching and micro-electroforming was studied and compared. The side wall of microstructures prepared by chemical micro-etching was irregular arc, and the size uniformity was relatively poor. The surface roughness is larger than Ra3.58 渭 m, while the side wall of the microstructure prepared by micro-electroforming is regular trapezoid, the dimension uniformity is good, the surface roughness is lower than Ra 0.65 渭 m. The metal die of microfluidic chip prepared by microelectroforming is better than that of chemical micro-etching in aspect of sidewall steepness, dimension uniformity and roughness of microstructure. The experiment scheme of controlling power pulse frequency and pulse waveform in electroforming process is adopted. The fabrication process of micro / nano structure on the surface of mold runner of microfluidic chip was studied. The microchannel with certain size surface micro / nano structure could be fabricated with high frequency and a certain pulse waveform.
【学位授予单位】：广东工业大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TQ153.4

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