NER: Manipulation and 3D Organization of Nanoparticles Using Dielectrophoresis

该项目是响应纳米尺度科学与工程计划（NSF 01-157， NER类别）而收到的，它涉及纳米颗粒的操作和组织。将胶体颗粒组织成一维、二维和三维有序结构，是制造大量具有重要技术意义的小型化产品的第一步。结构属性，如长程有序，高填料密度，高表面体积比，可复制的形状和尺寸是非常理想的。力显微镜和光学镊子已被用于操纵少数单个颗粒，而胶体结晶和模板已被用于颗粒组织；然而，巨大的挑战依然存在。我们的目标是开发一种方法，利用非均匀电场（介质电泳，DEP）将纳米颗粒组织成具有规定长度尺度和组成的明确的二维和三维有序结构（例如金字塔，平行六面体）。这种方法是可扩展和易于自动化的，并且允许以纳米级顺序制造功能材料，可用于其结构特性，例如，光子材料或高密度数据记录设备，和/或其结构，例如，朝向更复杂设备的预制块（“自下而上”策略）。我们将遵循一个系统的方法，从2D到3D顺序，从微粒到纳米颗粒。这项研究具有探索性和高风险，因为在组织过程中产生的力可能会使DEP效应失效，并且有效组织纳米颗粒所需的电极尺寸可能具有挑战性。这项研究将通过(a)使用DEP制造具有层次顺序的纳米结构，以及(b)开发在大规模制造中有效实施DEP的工艺设计工具，在纳米技术领域取得重大进展。参与该项目的研究生和本科生将获得宝贵的经验，而工业界（和社区）将受益于通过这项研究在大学开发的纳米结构和纳米制造方面的专业知识。

This project was received in response to Nanoscale Science and Engineering initiative, NSF 01-157, category NER, and it addresses the manipulation and organization of nanoparticles. The organization of colloidal particles into one-, two- and three-dimensional ordered structures represents the first step towards the fabrication of a large number of miniaturized products of great technological importance. Structural attributes such as long-range order, high packing density, high surface-to-volume ratio, and reproducible shape and dimensions are highly desirable. Force microscopy and optical tweezers have been used for the manipulation of a small number of individual particles, while colloidal crystallization and templating have been used for particle organization; however, big challenges remain. Our goal is to develop a methodology that utilizes nonuniform electric fields (dielectrophoresis, DEP) to direct the organization of nanoparticles into well-defined two- and three-dimensional ordered structures (e.g., pyramids, parallelepipeds) with prescribed length scales and composition. Such methodology is scalable and readily automated, and would allow the manufacturing of functional materials with nanometer-scale order that can be used for their structural properties, e.g., photonic materials or high density data recording devices, and/or their structure, e.g., prefabricated blocks towards more complicated devices ("bottom up" strategy). We will follow a systematic approach, from 2D to 3D order and from microparticles to nanoparticles. This research is exploratory and high risk since forces developed during the organization process may nullify the DEP effect, and the dimensions of the electrodes required for the efficient organization of nanoparticles may be challenging to fabricate.This research should lead to significant advancements in the field of nanotechnology by the (a) fabrication of nanostructures having hierarchical-order using DEP, and (b) development of process design tools for efficient implementation of DEP in large-scale manufacturing. The graduate and undergraduate students who will be involved in the project will gain valuable experience, while industry (and the community) will benefit from the expertise on nanostructures and nanomanufacturing developed at the university through this research.