基于局部加热的聚合物微流控通道引导自封闭方法研究

发布时间：2018-03-24 06:16

本文选题：微流控通道　切入点：湿法腐蚀　出处：《合肥工业大学》2015年硕士论文

【摘要】：微纳米通道是微流控芯片的重要组成部分,由于流体在微尺度下具有不同于一般宏观尺度下的流动特性,因而具有许多重要应用。选择何种微纳米加工工艺从而准确、高效的获得微纳米通道成为研究的热点问题。本文以各种微纳米加工技术为主体,在玻璃基底上制备PMMA的沟槽微结构图形,并通过局部加热方式获得PMMA的微通道结构。在PMMA沟槽微结构图形的制备过程中,首先使用湿法腐蚀技术制备出单晶硅的沟槽微结构模板,其次采用紫外固化压印光刻技术(UV-NIL)在PET表面制备PUA沟槽微结构的模板,最后利用热压纳米压印技术(HE-NIL)在玻璃基片表面制备出PMMA沟槽微结构图形。在该实验过程中,分别介绍了各个工艺中实验操作及其注意事项,并阐述了各种因素对实验结果的影响。其中,基于粘附能理论对PUA模板的制备过程进行了详细分析,得出成功复制的临界深宽比,最终通过表面改性成功复制出高深宽比的PUA沟槽微结构。在PMMA沟槽微结构图形的封闭过程中,利用自制的简易设备对PMMA沟槽微结构图形顶部进行局部加热,顶部的聚合物融化后在表面张力和硅片挤压的作用下沿着沟槽侧壁往下流动,最终毛细力与大气的压力平衡形成微通道。针对实验过程中的传热问题,建立了半无限大物体瞬态传热模型,得到硅片与基片间合理相对运动速度。忽略融化后聚合物体积变化,建立几何模型探讨了微通道尺寸的控制。此外,还探究了硅片与基片间的相对运动方向与聚合物线条方向平行或垂直对于微通道制备效果的影响。这些研究为该实验提供必要的理论指导,有望为微纳米通道的制备提供了一种新方法。
[Abstract]:Microchannel is an important part of microfluidic chip. Because of the flow characteristics of fluid in microscale, it has many important applications. It has become a hot issue to obtain PMMA microchannels efficiently. In this paper, the grooves of PMMA are fabricated on glass substrates, and the microchannel structures of PMMA are obtained by means of local heating. In the preparation of PMMA grooves, the grooves of monocrystalline silicon were fabricated by wet etching and UV-NILs were used to fabricate the templates of PUA grooves on the surface of PET. Finally, PMMA groove microstructures were fabricated on the surface of glass substrate by hot embossing nano-imprint technique (HE-NILL). In the process of the experiment, the experimental operation and the points for attention in each process were introduced, respectively. The influence of various factors on the experimental results is discussed. The preparation process of PUA template is analyzed in detail based on the theory of adhesion energy, and the critical aspect ratio for successful replication is obtained. Finally, the PUA grooves with high aspect ratio were successfully copied by surface modification. In the process of sealing the PMMA grooves, the top of the PMMA grooves is locally heated by a simple and convenient device made by ourselves. The top polymer melts and flows down the side wall of the trench under the action of surface tension and silicon wafer extrusion. Finally, the capillary force is balanced with the atmospheric pressure to form a microchannel. The transient heat transfer model of semi-infinite object is established, and the reasonable relative velocity between silicon wafer and substrate is obtained. The geometry model is established to study the control of the size of microchannel, ignoring the volume change of polymer after melting. The effects of the relative direction of motion between the wafer and substrate on the preparation of microchannels are also investigated, which provide the necessary theoretical guidance for the experiment. It is expected to provide a new method for the preparation of micro-and nano-channels.
【学位授予单位】：合肥工业大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TN492

【共引文献】