NER: Manipulation and 3D Organization of Nanoparticles Using Dielectrophoresis

该项目是对纳米科学和工程倡议的响应，NSF 01-157，NER类，它涉及纳米颗粒的操纵和组织。将胶体粒子组织成一维、二维和三维有序结构是制造大量具有重要技术意义的微型化产品的第一步。结构属性，如长程有序，高堆积密度，高表面积体积比，以及可重复的形状和尺寸是非常理想的。力显微镜和光学镊子被用于操纵少量的单个颗粒，而胶体结晶和模板被用于颗粒组织；然而，巨大的挑战仍然存在。我们的目标是开发一种方法，利用非均匀电场(介电泳法，DEP)将纳米颗粒组织成定义良好的二维和三维有序结构(例如，金字塔、平行六面体)，并具有指定的长度、比例和组成。这种方法是可扩展的且容易实现自动化，并且将允许制造纳米级有序的功能材料，其可用于其结构特性，例如光子材料或高密度数据记录器件，和/或其结构，例如指向更复杂器件的预制块(“自下而上”策略)。我们将遵循一种系统的方法，从2D到3D顺序，从微粒到纳米颗粒。这项研究是探索性的和高风险的，因为在组织过程中产生的力可能会抵消DEP效应，并且有效组织纳米颗粒所需的电极的尺寸可能对制备具有挑战性。这项研究将通过(A)使用DEP制造具有层次化有序的纳米结构，以及(B)开发工艺设计工具来在大规模制造中有效地实施DEP，从而在纳米技术领域带来显著的进步。将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)将从大学通过这项研究开发的纳米结构和纳米制造方面的专业知识中受益。

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.