面向微纳加工应用的硅藻仿生表面自组装黏附机制与力学性能研究

Microbial bionic assembly is an important method and research frontier for MEMS micro/nano fabrication. At present, the research of bionic micro/nano processing mainly focuses on simulating biological body and functional structure, using traditional mechanical processing or additive manufacturing method. The efficiency is relatively low, and it is difficult to accurately control the processing of complex structure and interface at micro/nano scale. Herein, we take marine benthic diatom and MEMS substrate as research objects, the orientation and immobilization of diatom on the surface of MEMS substrate will be achieved by understanding and controlling the interaction between the surface microstructure, surface energy, hydrophilicity characteristics and the movements and adhesion behaviors of diatoms. Based on the theories of material-cell interactions, the mechanical properties and regulation mechanism of the bonding interface between diatom/frustule and substrate will be studied. Through the optimization of the surface self-assembly of special benthic diatom, the accurate orientation and fixation of frustule on the substrate will be achieved, which could be used for manufacturing of complex micro/nano-structures. This research project is aiming to provide an important scientific solution for high efficiency, low cost and precision machining of micro/nano fabrication, which has an important scientific significance.Microbial bionic assembly is an important method and research frontier for MEMS micro/nano fabrication. At present, the research of bionic micro/nano processing mainly focuses on simulating biological body and functional structure, using traditional mechanical processing or additive manufacturing method. The efficiency is relatively low, and it is difficult to accurately control the processing of complex structure and interface at micro/nano scale. Herein, we take marine benthic diatom and MEMS substrate as research objects, the orientation and immobilization of diatom on the surface of MEMS substrate will be achieved by understanding and controlling the interaction between the surface microstructure, surface energy, hydrophilicity characteristics and the movements and adhesion behaviors of diatoms. Based on the theories of material-cell interactions, the mechanical properties and regulation mechanism of the bonding interface between diatom/frustule and substrate will be studied. Through the optimization of the surface self-assembly of special benthic diatom, the accurate orientation and fixation of frustule on the substrate will be achieved, which could be used for manufacturing of complex micro/nano-structures. This research project is aiming to provide an important scientific solution for high efficiency, low cost and precision machining of micro/nano fabrication, which has an important scientific significance.

微生物仿生实现精准阵列化组装是微机电器件微纳加工制造的重要手段和研究前沿。目前的仿生微纳加工研究主要集中在模拟生物形体与功能结构，利用传统机械加工或增材制造方法进行加工，效率通常较低，很难对微纳复杂形体、结构、功能界面的加工进行精确操控。本项目以特种底栖硅藻和微机电衬底为研究对象，通过探讨衬底表面微观结构、表面能、亲疏水特性与硅藻主动趋向黏附行为的关联关系以及硅藻壳壁与衬底的键合作用，来指导硅藻硅质壳在衬底上的精确阵列化固定。基于生物与材料表面相互作用理论，系统研究硅藻在衬底上的表界面黏附行为和调控机制及去有机质处理后硅藻硅质壳微纳元件与衬底键合的界面力学性能。通过特种底栖硅藻仿生表面自组装优化，实现微纳元件在衬底上的精确阵列化固定，为高效率、低成本、精准化微纳加工提供重要的科学依据，具有重要的科学意义。

仿生制造是解决微纳器件加工制造技术这一难题的关键，而目前的仿生微纳加工研究主要集中在形貌或结构的模拟，其后续的加工制造方法效率低下且难以精确操控。因此，有必要寻求新途径解决此难题。硅藻作为一种单细胞自养型生物，其可在常温常压的水环境中合成纳米至微米尺度并且具有高度的规律性和精确重现性的刚性硅质壳。由于所形成的硅质壳拥有诸多优异的性能，其可被考虑直接作为一种微机电系统元件应用。本项目直接利用生物体对微纳器件加工制造技术的难题进行探究和突破，旨在构建一种作为仿生微机电系统元件的硅质壳在衬底上的可控阵列化精确固定方法和理论体系。本项目通过改变衬底表面的表面能、电荷和极性等条件测定了硅藻在不同修饰改性衬底表面的黏附效率和黏附强度，并对硅藻在基底表面的附着行为及机制进行研究，提出了Chaetoceros gracilis和Cyclotella cryptica两种硅藻的附着行为模型；首次对利用刻蚀图案化衬底的方法进行硅藻自组装行为进行了研究研究，得到了一种能有效诱导硅藻细胞选择性黏附的衬底制备方法；通过硅藻对定点光照的趋向特性进行的自组装研究，明确了外界条件对附着行为的影响及影响机理。该研究结果可为硅藻的附着控制研究提供新的思路，为解决硅质壳作为仿生微纳器件的加工制造问题提供了一种新的方案。