Aubry N, Singh P, Janjua M, Nudurupati S
Department of Mechanical Engineering, Carnegie Mellon University, Pittsburgh, PA 15213, USA.
Proc Natl Acad Sci U S A. 2008 Mar 11;105(10):3711-4. doi: 10.1073/pnas.0712392105. Epub 2008 Mar 4.
As chips further shrink toward smaller scales, fabrication processes based on the self-assembly of individual particles into patterns or structures are often sought. One of the most popular techniques for two-dimensional assembly (self-assembled monolayers) is based on capillary forces acting on particles placed at a liquid interface. Capillarity-induced clustering, however, has several limitations: it applies to relatively large (radius > approximately 10 microm) particles only, the clustering is usually non-defect-free and lacks long-range order, and the lattice spacing cannot be adjusted. The goal of the present article is to show that these shortcomings can be addressed by using an external electric field normal to the interface. The resulting self-assembly is capable of controlling the lattice spacing statically or dynamically, forming virtually defect-free monolayers, and manipulating a broad range of particle sizes and types including nanoparticles and electrically neutral particles.
随着芯片进一步向更小尺寸缩小，人们常常寻求基于单个粒子自组装成图案或结构的制造工艺。二维组装（自组装单分子层）最流行的技术之一是基于作用于置于液体界面处粒子的毛细作用力。然而，毛细作用诱导的聚集存在若干局限性：它仅适用于相对较大（半径>约10微米）的粒子，聚集通常并非无缺陷且缺乏长程有序性，并且晶格间距无法调整。本文的目的是表明，通过使用垂直于界面的外部电场可以解决这些缺点。由此产生的自组装能够静态或动态地控制晶格间距，形成几乎无缺陷的单分子层，并操控包括纳米粒子和电中性粒子在内的广泛粒径和类型的粒子。
