Zhang Xin-Ran, Deng Hai-Tao, Wen Dan-Liang, Zeng Xu, Wang Yi-Lin, Huang Peng, Zhang Xiao-Sheng
School of Integrated Circuit Science and Engineering, University of Electronic Science and Technology of China, Chengdu 611731, China.
Langmuir. 2023 Aug 1;39(30):10660-10669. doi: 10.1021/acs.langmuir.3c01322. Epub 2023 Jul 19.
Self-assembly is an important bottom-up fabrication approach based on accurate manipulation of solid-air-liquid interfaces to construct microscale structures using nanoscale materials. This approach plays a substantial role in the fabrication of microsensors, nanosensors, and actuators. Improving the controllability of self-assembly to realize large-scale regular micro/nano patterns is crucial for this approach's further development and wider applications. Herein, we propose a novel strategy for patterning nanoparticle arrays on soft substrates. This strategy is based on a unique process of liquid film rupture self-assembly that is convenient, precise, and cost-efficient for mass manufacturing. This approach involves two key steps. First, suspended liquid films comprising monolayer polystyrene (PS) spheres are realized via liquid-air interface self-assembly over prepatterned microstructures. Second, these suspended liquid films are ruptured in a controlled manner to induce the self-assembly of internal PS spheres around the morphological edges of the underlying microstructures. This nanoparticle array patterning method is comprehensively investigated in terms of the effect of the PS sphere size, morphological effect of the microstructured substrate, key factors influencing liquid film-rupture self-assembly, and optical transmittance of the fabricated samples. A maximum rupture rate of 95.4% was achieved with an optimized geometric and dimensional design. Compared with other nanoparticle-based self-assembly methods used to form patterned arrays, the proposed approach reduces the waste of nanoparticles substantially because all nanoparticles self-assemble around the prepatterned microstructures. More nanoparticles assemble to form prepatterned arrays, which could strengthen the nanoparticle array network without affecting the initial features of prepatterned microstructures.
自组装是一种重要的自下而上的制造方法，基于对固-气-液界面的精确操控，使用纳米级材料构建微尺度结构。这种方法在微传感器、纳米传感器和致动器的制造中发挥着重要作用。提高自组装的可控性以实现大规模规则的微/纳米图案对于该方法的进一步发展和更广泛应用至关重要。在此，我们提出了一种在软基板上对纳米颗粒阵列进行图案化的新策略。该策略基于液膜破裂自组装的独特过程，对于大规模制造而言既方便、精确又具有成本效益。这种方法涉及两个关键步骤。首先，通过在预先图案化的微结构上进行液-气界面自组装，实现由单层聚苯乙烯（PS）球体组成的悬浮液膜。其次，以可控方式使这些悬浮液膜破裂，以诱导内部PS球体围绕下层微结构的形态边缘进行自组装。从PS球体尺寸的影响、微结构化基板的形态效应、影响液膜破裂自组装的关键因素以及所制备样品的光学透过率等方面对这种纳米颗粒阵列图案化方法进行了全面研究。通过优化的几何和尺寸设计，实现了95.4%的最大破裂率。与用于形成图案化阵列的其他基于纳米颗粒的自组装方法相比，所提出的方法大大减少了纳米颗粒的浪费，因为所有纳米颗粒都围绕预先图案化的微结构进行自组装。更多的纳米颗粒组装形成预先图案化的阵列，这可以加强纳米颗粒阵列网络，而不会影响预先图案化微结构的初始特征。
