微器件的制作和微电铸均匀性的研究

发布时间：2018-03-19 02:22

  本文选题：MEMS　切入点：微针　出处：《大连理工大学》2015年硕士论文　论文类型：学位论文

【摘要】：微型化、集成化和便携化是科技发展的一种趋势,微机电系统(Micro Electro Mechanical System, MEMS)工艺是实现器件微型化、集成化和便携化的重要手段。在MEMS众多研究方向中,因生物MEMS应用潜力大、科技优势显著成为研究的热点之一。其中基于MEMS工艺的微针和微流控芯片是生物MEMS医学应用研究的典型器件。背面曝光技术和微电铸技术分别是制作微针和微流控芯片模具的关键技术,然而背面曝光制作微针的技术尚不成熟,电铸技术也存在着铸层厚度不均匀的问题,严重制约了微针和微流控芯片在生物医学方面的应用。本文使用模拟软件Matlab和COMSOL并结合实验研究,探究优化基于背面曝光工艺制作微针的成型方法和改善电沉积均匀性的可行性措施。本文的研究工作可以为MEMS生物医学的进一步发展积累经验。本文基于标量角谱衍射理论,利用Matlab软件进行了圆孔衍射的模拟,确定了定值圆孔制作微针的最佳衍射光场范围。通过调整基底厚度、曝光剂量等参数,制作了高度从265μm到380μm,倾角从5.1°到15.6°,底端直径远大于掩膜版上对应圆孔直径的SU-8胶微针阵列。用微针侧壁倾角和顶部直径与掩膜版上圆孔直径的比值R评价微针的尖锐程度,分析并讨论了实验中遇到的问题。利用电沉积理论和法拉第第一定律推导了电流密度分布与铸层厚度分布的关系。基于电流密度数值分布模型,采用COMSOL模拟软件,研究了辅助阴极对阴极电力线和电流密度分布的影响并对辅助阴极结构进行了优化,预测了铸层形貌。为验证仿真结果,采用控制变量法设计了比对实验,用电感测微仪测量了电铸后的铸层厚度,实验结果与仿真结果趋势相同,结果表明：微电铸模具的铸层厚度不均匀度由142.0%缩减至68.9%。基于微电铸技术制作了厚度为200μm的镍金属模具。为实现微流控芯片模具的纳米结构定域加工,改善其表面性能,使用飞秒激光加工技术在镍模具表面加工了微纳米结构,实现了镍模具部分表面由亲水性向疏水性的转变。使用热压印技术实现了微纳米结构从镍模具到PMMA的精确复制和转移,使用水预处理键合技术提高了PMMA微流控芯片的键合率,最后使用CO2激光加工技术对键合后的芯片进行了外形轮廓的加工,制得了应用于病原微生物检测的微流控芯片。
[Abstract]:Miniaturization, integration and portability are a trend in the development of science and technology. MEMS Micro Electro Mechanical system is an important means to realize the miniaturization, integration and portability of devices. The advantage of science and technology has become one of the hotspots in the research. Microneedle and microfluidic chip based on MEMS process are typical devices in biomedical application of MEMS. Back exposure technology and microelectroforming technology are the fabrication of microneedle and microflow, respectively. The key technology of controlling chip mould, However, the technology of making microneedle by back exposure is not mature, and the electroforming technology also has the problem of uneven thickness of casting layer. The application of microneedle and microfluidic chip in biomedicine is seriously restricted. In this paper, the simulation software Matlab and COMSOL are used in combination with experimental research. This paper explores the feasibility measures to optimize the fabrication of microneedles based on the back exposure process and to improve the uniformity of electrodeposition. The research work in this paper can accumulate experience for the further development of MEMS biomedicine. This paper is based on the scalar angular spectrum diffraction theory. The Matlab software is used to simulate the diffraction of circular holes, and the optimum range of diffraction light field is determined. By adjusting the thickness of the substrate, the exposure dose and other parameters, the optimum range of diffraction light field is determined. A SU-8 microneedle array with a height of 265 渭 m to 380 渭 m and a dip angle of 5.1 掳to 15.6 掳was fabricated. The diameter of the bottom end was much larger than the corresponding diameter of the circular hole on the mask plate. The sharp degree of the microneedle was evaluated by the inclination angle of the sidewall of the microneedle and the ratio of the top diameter to the diameter of the hole on the mask plate. The relationship between the distribution of current density and the thickness distribution of cast layer is derived by using the theory of electrodeposition and Faraday's law. Based on the model of numerical distribution of current density, the simulation software COMSOL is used. The influence of the auxiliary cathode on the distribution of power line and current density of the cathode is studied, and the structure of the auxiliary cathode is optimized, and the shape of the cast layer is predicted. In order to verify the simulation results, the control variable method is used to design the comparison experiment. The thickness of the cast layer was measured by electroforming micrometer. The experimental results are the same as the simulation results. The results show that the thickness inhomogeneity of cast layer of microelectroforming die is reduced from 142.0% to 68.9. Based on microelectroforming technology, nickel metal dies with thickness of 200 渭 m have been fabricated. Using femtosecond laser processing technology, the micro and nano structure was fabricated on the surface of nickel mould, and the partial surface of nickel mould was changed from hydrophilicity to hydrophobicity. The accurate replication and transfer of micro and nano structure from nickel mould to PMMA was realized by hot stamping technology. The bonding rate of PMMA microfluidic chip was improved by water pretreatment bonding technology. Finally, the profile of the bonded microfluidic chip was processed by CO2 laser processing technology, and the microfluidic chip was prepared for the detection of pathogenic microorganism.
【学位授予单位】：大连理工大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TN492

【参考文献】

中国期刊全文数据库 前6条

1 杨建明;;电沉积分布均匀性改善技术的研究进展[J];材料保护;2010年04期

2 马鑫;蒋炳炎;陈中原;吕辉;Stefan Kirchberg;;屏蔽挡板对电铸微模芯厚度均匀性的影响[J];电镀与环保;2014年05期

3 王飞;邓小玖;刘彩霞;谢莉莎;;标量衍射理论的非傍轴修正[J];量子电子学报;2007年01期

4 赵阳培,黄因慧,赵剑峰,刘志东,田宗军;射流电铸快速成型基础试验研究[J];南京航空航天大学学报;2004年04期

5 刘冲;刘文涛;杜立群;莫顺培;;一种三维金属微型腔的组合加工方法[J];纳米技术与精密工程;2010年01期

6 刘伟;王伊卿;甘代伟;;刚性模具纳米热压印直接成型技术研究与应用[J];陕西国防工业职业技术学院学报;2010年03期

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