SGER: Fabrication and Characterization of Asymmetric Nanoscale Surface Structures

自然界提供了许多有趣的例子，液体与纳米图案表面相互作用，以实现各种功能，如排斥水和污染物。 另一方面，纳米技术使得能够制造纳米级表面结构，其可以显著改变表面疏水性或亲水性。该SGER提案的目的是探索纳米制造方法，以制造具有不对称特征的纳米级表面结构，并表征其对液体-表面相互作用的影响。一个两步，新颖的光刻方法将在这项研究中开发。深反应离子蚀刻（DRIE）将用于在单晶硅晶片上产生高纵横比、不对称的表面特征。将探讨不同的不对称模式。将进行测量，以表征这些表面的疏水性变化作为不对称特征的函数。人们期望这样的表面结构可以用来实现在工程材料和结构的今天不提供的功能。理解液滴和图案化表面之间的相互作用将有助于解决纳米科学和纳米技术中的重要问题。该项目开发的制造方法将为创建复杂的表面纳米结构铺平道路。了解在不对称表面纳米结构存在下的液-固表面相互作用的机制将提供可以自清洁的材料，或者可以用于排斥或收集液体的表面结构。此外，在拟议的探索性研究中培养研究生，使他们有机会体验科学研究的各个阶段，这将有利于他们未来的职业生涯。

Nature provides many interesting examples of liquid interacting with nano-patterned surfaces to achieve a variety of functions such as repelling water and contaminants. Nanotechnology, on the other hand, enables manufacturing of nanoscale surface structures that could significantly alter surface hydrophobicity or hydrophilicity. The objective of this SGER proposal is to explore nanomanufacturing methods to fabricate nanoscale surface structures with asymmetric features and characterize their effects on liquid-surface interactions. A two-step, novel lithography method will be developed in this study. Deep reactive ion etching (DRIE) will be employed to produce high aspect ratio, asymmetric surface features in single crystalline silicon wafer. Different asymmetric patterns will be explored. Measurements will be carried out to characterize the hydrophobicity change of these surfaces as a function of asymmetric features. It is expected that such surface structures could be utilized to achieve functionalities that are not available in engineered materials and structures today.Understanding the interactions between liquid droplets and patterned surfaces will help address important issues in nanoscience and nanotechnology. The manufacturing method developed in this project will pave the way to creating complex surface nanostructures. Understanding the mechanisms of liquid-solid surface interactions in the presence of asymmetric surface nanostructures will provide materials that could be self-cleaning, or surface structures that may be used to repel or collect liquid. Moreover, training of graduate students in the proposed exploratory research gives them the chances to experience the progressive stages of scientific research, which will benefit their career in the future.