基于纳米粒子改性的弹性基底上金属微电极制造理论与方法研究

Polydimethylsiloxane (PDMS) is a high-elasticity organosilicon compound. PDMS is not compatible with semiconductor manufacturing technologies in thermal and surface properties, which makes it very difficult to fabricate metal microelectrodes on PDMS substrates, and greatly limits the application of electrochemical detection for PDMS microfluidic chips. Therefore, a new fabrication method for metal microelectrodes on PDMS substrates based on the modification of nanoparticles is presented. Through doping PDMS substrates with nanoparticles, the thermal expansion coefficient of PDMS will be decreased, and thus the wrinkling of metal films and cracking of the photoresist on PDMS substrates caused by the great thermal mismatch can be prevented. At the same time, the surface energy of PDMS will also be increased, which can improve the wetting characteristics of the photoresist on PDMS. The mechanism for generating the thermal stress in metal films on PDMS substrates will be studied, the mechanical analysis model will be built, and combining with the finite element analysis, the wrinkling mechanism of the metal film will be discovered. The effects and mechanism of the modification of nanoparticles on the properties of PDMS will be examined. Combining theories and processing experiments, a new method for fabricating metal microelectrodes on PDMS substrates will be finally demonstrated. Several kinds of PDMS microfluidic chips will be fabricated by this method. The achievements of this project will contribute to the advancement of the microfluidic chip technology, and also have great significance in theories and applications for the fields of both thin film materials and flexible electronics.

聚二甲基硅氧烷（PDMS）是一种高弹性有机硅化合物，在热性能和表面特性等方面与半导体工艺不兼容，导致难以在PDMS基底上制作金属微电极，严重限制了电化学检测方法在PDMS微流控芯片上的应用。为此，本项目首次提出一种基于纳米粒子改性的弹性基底上金属微电极制造新方法。通过在PDMS中掺杂纳米粒子，减小PDMS的热膨胀系数，从而解决由于热失配过大导致的PDMS表面金属薄膜和光刻胶上出现的皱褶和裂纹问题。同时有助于提高PDMS表面能，改善光刻胶在其表面的浸润性。阐明PDMS上沉积的金属薄膜热应力产生机制，建立力学分析模型，并结合有限元分析揭示金属薄膜褶皱的形成机理。研究纳米粒子改性对于PDMS性能的影响规律及作用机理。结合理论和实验，最终建立一套在PDMS上制作金属微电极的新方法。利于该方法，研制多种微流控芯片。成果将促进微流控芯片技术发展，对于薄膜材料和柔性电子领域也具有重要理论意义和应用价值。

聚二甲基硅氧烷（PDMS）是一种高弹性有机硅化合物，在热性能和表面特性等方面与半导体工艺不兼容，导致难以在 PDMS 基底上制作金属微电极，严重限制了电化学检测方法在 PDMS 微流控芯片上的应用。为此，本项目提出了一种基于纳米粒子改性的弹性基底上金属微电极制造新方法。通过在 PDMS 中掺杂纳米粒子，减小 PDMS 的热膨胀系数，从而解决了由于热失配过大导致的 PDMS 表面金属薄膜出现皱褶等问题。揭示了金属薄膜产生褶皱的机理，阐明了纳米粒子改性对于 PDMS 性能的影响规律及作用机理，建立了一套在 PDMS表面制作金属微电极的方法。利于该方法，研制出了2种集成金属微电极的PDMS微流控芯片和1种集成金属微电极的纳流控电化学传感芯片，并开展了相应的应用研究。在本项目的资助下，共发表SCI收录论文13篇，其中中科院SCI分区一区论文3篇，申请国家发明专利3项。